Featured
Sponsor

 

 

 
FAQs about Bubble Trouble and Aquarium Systems 2

Related Articles: Plumbing Marine Systems, Plumbing Return Manifolds, Refugiums, 

Related FAQs: Bubble Troubles 1, Marine Plumbing 1, Marine Plumbing 2, Marine Plumbing 3,  Marine Plumbing 4, Marine Plumbing 5, Marine Plumbing 6, Plumbing 7, Plumbing 8, Plumbing 9, Plumbing 10, Plumbing 11, Plumbing 12, Plumbing 13, Plumbing 14, Plumbing 15, Plumbing 16, Plumbing 17, Plumbing 18, Holes & Drilling, Durso Standpipes, Overflow Boxes, Plumbing Noise, Make Up Water Systems, Pumps, Plumbing, Circulation, Sumps, Refugiums, Marine Circulation 2, Gear Selection for Circulation, Pump Problems, Fish-Only Marine Set-ups, Fish-Only Marine Systems 2, FOWLR/Fish and Invertebrate Systems, Reef Systems, Coldwater Systems, Small Systems, Large Systems, Water Changes, Surge Devices, 


El Sapo sez: "Me no like bubbles, no no."

Noise Level and "Micro" Bubbles 4/29/08
Thanks for your guidance in the past in setup.
<You’re welcome.>
I have two questions about my still lifeless tank. I have a used Dutch AS 75 G flat back hex tank which I restained and varnished, drilled for two 1.5 bulkheads in the top corners. 90 pounds of very cured Live Fiji rock. I have installed it with two overflow PVC 1.5 pipes running from L’s at the bulkhead. Each L has a 1/4 inch John Guest Air valve to allow air suction into the 90s and prevent "burping".
<Is the airline run down into the drain line?>
The pipes run down to a 30 gallon 30X18X12 sump/refugium, which is turning out to be too tall. One pipe goes directly to the 12 inch ASM G2 skimmer chamber (right side of sump); one passes the 9 inch refugium (left side of sump) with a teed 3/4 inch ball valve dropping a few gph into the fuge, and then continues to the skimmer chamber. Middle chamber is a 6 inch pump chamber housing an OR6500 pump. Bubble trap baffles between the skimmer and the pump chamber, although I made these too narrow and may be promoting too rapid flow.
<This can be a problem with not enough dwell time through the baffles to allow the bubbles to escape. Foam between two of the baffles can make a huge difference.>
Exhaust enters the sump below the waterline from the 2 1.5 drain lines but is dropping a lot of bubbles.
<They will, this needs to be managed.>
Some appear to be making it past the trap and back into the tank. I did not build a bubble chamber for the skimmer section, and I have not employed socks, because the sump is so tall I would have a hard time accessing/changing them, and would turn them into nitrate sources.
<This too can be a big help for you. You will need either a filter sock (even if it is a pain to change) or to fabricate something your drains can dump into forcing the water and air to come back up before transiting the rest of the sump. I used to have my overflow dump into a 1 liter bottle with the top cut off for this purpose!>
OR6500 pumps 1.25 line out through 6 inches of flex, threaded connection, union, ball valve, 2 45s, 3 foot rise, tees at the top of the tank into two 1s and drops water into the tank about an inch below the surface. Both sides are blasting microbubbles.
<Frustrating.>
In order to reduce bubbles I have tried vaselining pressure-side joints to check for any venturi above the sump waterline and found none. I have damped flow down from the refugium and seen minimal impact. I suspect the problem is with the volume speed through the baffles.
<It is sounding that way.>
So much for background:
1) Short of reengineering my sump, which may be inevitable, what other suggestions can you offer to reduce bubbles ?2) I have not seen much foam or skimmate in my ASM. I only have a few hermits and snails aside from the LR so there is not much to skim. Is it true that fresh salt water takes some time to "ripen" and reduce surface tension and that the skimmer and bubbles will improve over time?
<Yes, more of the components in the tank being new with manufacturing residues floating about.>
3) I don't have overflow boxes, just two 90s acting as drains which are currently level with the waterline. They are loud. Is there any trick to minimize their noise level?
<First, be sure the open end of the elbow is pointing down into the water. This will keep the inside of the line from being exposed to the atmosphere and your ears. Next you may need to experiment a bit with the air inlets on the elbows. John Guest fittings are nice, but you will need to be able to run the airline down into the elbow a bit. How far down for your case it the experimental part, you will need to play with this distance until the overflow is quiet. Generally 4” down in from the top of the elbow will get you fairly close for this amount of flow. Your drains are sized well for this pump, you can get these quiet.>
Thanks, as always, John.
<Welcome John. You have a bit of playing to do, but this flow can be managed through a sump this size. It is just all about directing it, making the bubbles work around obstacles to get into the return pump. Keep with it, good luck, Scott V.>

Re: Noise Level and "Micro" Bubbles 5/6/08
Thanks for your guidance in the past in setup.
<You're welcome.>
I have two questions about my still lifeless tank. I have a used Dutch AS 75 G flat back hex tank which I restained and varnished, drilled for two 1.5 bulkheads in the top corners. 90 pounds of very cured Live Fiji
rock. I have installed it with two overflow PVC 1.5 pipes running from L's at the bulkhead. Each L has a 1/4 inch John Guest Air valve to allow air suction into the 90s and prevent "burping".
<Is the airline run down into the drain line?>
{no, just a gate valve on the ell. I will extend the line down into the pipe 4 inches}
<<This will make a big difference.>>
The pipes run down to a 30 gallon 30X18X12 sump/refugium, which is turning out to be too tall. One pipe goes directly to the 12 inch ASM G2 skimmer chamber (right side of sump); one passes the 9 inch refugium (left side of sump) with a teed 3/4 inch ball valve dropping a few gph into the fuge, and then continues to the skimmer chamber. Middle chamber is a 6 inch pump chamber housing an OR6500 pump. Bubble trap baffles between the skimmer and the pump chamber, although I made these too narrow and may be promoting too rapid flow.
<This can be a problem with not enough dwell time through the baffles to allow the bubbles to escape. Foam between two of the baffles can make a difference.>
{Wouldn't foam slow flow further? }
<<No, it will just serve the purpose to trap bubbles. Use the coarser filter type foams.>>
Exhaust enters the sump below the waterline from the 2 1.5 drain lines but is dropping a lot of bubbles.
<They will, this needs to be managed.>
{OK..........}
Some appear to be making it past the trap and back into the tank. I did not build a bubble chamber for the skimmer section, and I have not employed socks, because the sump is so tall I would have a hard time accessing/changing them, and would turn them into nitrate sources.
<This too can be a big help for you. You will need either a filter sock (even if it is a pain to change) or to fabricate something your drains
can dump into forcing the water and air to come back up before transiting the rest of the sump. I used to have my overflow dump into a 1 liter bottle with the top cut off for this purpose!>
{My space is cramped with a gate valve modded G2 but I will see if I can squeeze something in. }
<<Even a small cup that forces the air back up before the water is allowed to flow through the sump can have an impact.>>
OR6500 pumps 1.25 line out through 6 inches of flex, threaded connection, union, ball valve, 2 45s, 3 foot rise, tees at the top of the tank into two 1s and drops water into the tank about an inch below the surface. Both sides are blasting microbubbles.
<Frustrating.>
{Yup}
In order to reduce bubbles I have tried vaselining pressure-side joints to check for any venturi above the sump waterline and found none. I have damped flow down from the refugium and seen minimal impact. I suspect the problem is with the volume speed through the baffles.
<It is sounding that way.>
{Yup.}
So much for background:
1) Short of reengineering my sump, which may be inevitable, what other suggestions can you offer to reduce bubbles ?2) I have not seen much
foam or skimmate in my ASM. I only have a few hermits and snails aside from the LR so there is not much to skim. Is it true that fresh salt water takes some time to "ripen" and reduce surface tension and that the skimmer and bubbles will improve over time?
<Yes, more of the components in the tank being new with manufacturing residues floating about.>
{Actually only the Sedra is new. Everything else including the g2 body is used.}
<<Even that can impact skimmer performance, or you just don’t have much to skim as you mentioned. You’re water tests will tell you which.>>
3) I don't have overflow boxes, just two 90s acting as drains which are currently level with the waterline. They are loud. Is there any trick to minimize their noise level?
<First, be sure the open end of the elbow is pointing down into the water. This will keep the inside of the line from being exposed to the atmosphere and your ears. >
{Are you saying facing the tank bottom? Thant would place my overflows 8 inches below the waterline? Or are you simply saying 45 degrees from vertical like 10:30 and 1:30? }
<<However far you need to rotate them so the open end is underwater. Without boxes you may have to construct a little standpipe to get the desired water level. Be creative!>>
<Next you may need to experiment a bit with the air inlets on the elbows. John Guest fittings are nice, but you will need to be able to run the airline down into the elbow a bit. How far down for your case it the experimental part, you will need to play with this distance until the overflow is quiet. Generally 4" down in from the top of the elbow will get you fairly close for this amount of flow. Your drains are sized well for this pump, you can get these quiet.> Thanks, as always, John.
<Welcome John. You have a bit of playing to do, but this flow can be managed through a sump this size. It is just all about directing it, making the bubbles work around obstacles to get into the return pump.
Keep with it, good luck, Scott V.>
Thanks for your help.
{Thanks. I will try these suggestions.}
<<Welcome, good luck, Scott V.>>

Plumbing/Battling Micro Bubbles 4/10/08
Hello to the crew,
<And good day to you, Jeff>
I was hoping someone could help me with a closed loop issue. I am using the design from Melve's reef site where the water is drawn out of the overflow chamber in the tank. I have a 72 gal bow front with the standard overflow kit probably about 2 to 3 gallons (the tank is drilled for overflow 2 holes on bottom of tank, but not for closed loop). I have a Durso in the over flow so the chamber stays pretty full. I have a 20 gallon long sump with 3 chambers. I am using a Gen x mak-4 external (3/4" in/output) pump located under the tank. The loop is plumbed with ¾" PVC and the outputs are ½". I currently have 3 outputs set up for the closed loop. I can get the pump primed and it works well aside micro bubbles.
My issue is with micro bubbles. There are so many it is hard to see the back of the tank. I had 4 outputs, I went to three and I still have micro bubbles. I went back and made sure I had all the plumbing sealed that is not underwater. I used airline tubing to listen for leaks and could not find any. I wrapped filter media around the intake pipe on the system and placed filter media on the inside of the overflow so the water entering the overflow is not splashing but I am still getting tons of micro bubbles. They seemed to get worse when I resealed the plumbing. I am out of ideas and can not figure out where the bubbles are coming from. I was wondering if you had any other suggestions to get rid of the bubbles. If not I guess I will have to settle for power heads and sue the pump as a fancy door stop. Thanks for all your help and again great site!!!
<Your sump is more than likely full of bubbles from the overflow. I would isolate the section where the pump intake is located with a piece of foam whereby all water must pass through the foam to get to the pump intake. See if that doesn't help the matter. Also ensure the sump water level is high enough so a vortex isn't created above the pump intake.>
Kind Regards
<Thank you, James (Salty Dog)>
Jeff

Re: Plumbing/Battling Micro Bubbles 4/11/08
Hello again,
<Hi Jeff>
I think there was some miss understanding on my set up. The intake for the closed loop is located in the overflow chamber in the main tank. The intake is a 6 inch section of PVC with many holes drilled in it. It pulls water out of the overflow box in the tank, down to the pump and back into the main tank. The sump is not involved.
<Will be difficult here to completely eliminate the micro bubbles. Are any of the holes in the 6 inch section exposed to air? All holes need to be completely submerged.>
As I mentioned I have wrapped the loop intake with filter media, it is blue on one side and white on the other, so all water entering the loop has to pass through the filter media. I have also placed some filter media along the inside of the overflow box so there is no splashing as the water enters the overflow. You mentioned using foam, would this be any different then using the filter media? Would the foam be denser and stop more bubbles? Any special foam or will home depot have the right stuff?
<There are round foam sleeves available that slide directly over the intake tube will should reduce the micro bubbles a great deal. The availability will depend on the diameter/size of your intake tube. Example here.
http://www.premiumaquatics.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=PM-F46B&Category_Code=GFI In your particular set up, I believe it will be difficult to completely eliminate the micro bubbles. You may also want to try throttling down the return from the pump. You may be trying to pump out more water than is available to the pump. This will cause pump cavitation which will cause this problem. Try the foam sleeve for sure, will help.>
Thanks again for all your help.
<You're welcome. James (Salty Dog)>
Jeff Amato

Bubbles, Bubbles, Bubbles. 2/28/08
Good Morning WWM Crew!
<Hello Mike.>
I have a filtration issue I was hoping to get some input on.
<OK>
In my 125g FOWLR tank I am currently using two Aquaclear 110 filters along with two Hydor Koralia 4 powerheads for circulation. The issue is with the Aquaclear 110s. The water return, being the "waterfall" type of return, is creating massive amounts of bubbles from both filters upon return into the tank, which are then sent shooting all over the tank by the two powerheads.
<Not a good thing to have.>
It's really just an aesthetic issue really (I hope), and the tank just doesn't "look right" to me. Also, is there any issues for the fish and/or my inverts (hermits, peppermint shrimp, starfish) with these bubbles?
<It can be, see http://www.wetwebmedia.com/bubtroubfaqs.htm and the other related FAQ’s for more info on this.>
I have raised the water level to the limit (just slightly under the return flow), and it has helped a little, but it is still a big issue.
<Can you raise it up to the return flow to prevent the drop/splashing?>
I was wondering if there was any way to modify the filters to change the return water flow and cut down (or in a perfect world eliminate) the bubbles? I was hoping to not have to go to a new filter, and be able to make the existing filters work somehow (with less bubbles).
<Some hang on the back skimmers use boxes inside the tank to prevent these bubbles and they are fairly effective. You just find a small plastic container that will capture the water coming out of the filter and cut the bottom out. Then replace the bottom of the container with some filter foam. This will drastically help your bubble issues. Do be sure the top of this box is lower than the top of your tank, giving the water somewhere to go should the box overflow.>
I would appreciate any help and suggestions you could provide.
As always, thank you for the help and your time.
Mike P.
<Welcome, do try raising the water level a bit more first, this should really do the trick. Good luck, Scott V.>

AquaC EV240 Producing Microbubbles 2/16/08
Hello Gents - and thanks again for the fantastic resource. If only we all followed all the advice you give us!
<Heee…and if gas were back to $1 a gallon!>
Here's my dilemma - I have a 150XH fish only tank with a large wet dry and a Living Color coral insert.
I run an Aqua C EV 240 on my reef and have one for this tank as well.
I installed a new wet dry this week. Problem is that the skimmer is putting a tone of micro bubbles back into the display.
<Was it doing this before the new wet/dry? The same manufacturing residues/oils that can cause a new skimmer to spit out microbubbles are present in the new sump. You may just need some time.>
The sump is as follows - 40" long. From right to left, the tank drains into a 26" area of bio balls. I don’t have enough room in the cabinet, so I use a submersible Mag9 as the return pump. Due to the fact that the last area of the sump is the only 'open' area, it’s crowded. I have the Mag 9 tank return pump, the Ev240 and the Mag 18 that feeds the 240.
<According to the AquaC website this pump overdrives this skimmer and may need to be throttled down a bit. This could be playing a factor in bubble return.>
The skimmer water returns right to the area where the tank return pump is.
<Tough situation, even the slightest amount of bubbles will be returned to the tank.>
Unfortunately, I have VERY little space in that open area so I'm hoping to solve this problem.
Any ideas? I can call Jason Kim on Monday as well.
Thanks
J
<I would definitely contact Jason Kim for his input. In the meantime, you may want to try either some filter foam or filter sock types of materials between the skimmer output and the return pump to help catch the bubbles. Welcome and good luck, Scott V.>

Micro-bubbles/gas-bubble disease  2/15/08
Hi,
<Hello Ryan>
I've been breeding marines for a while and I recently set-up a 10 x 55g system to house the majority of my common broodstock (clowns, Dottybacks etc.) and I have been having a bit of a problem with micro-bubbles. I have tried many things to try and rectify this problem and am starting to suspect that I purely have too much flow going through the system. I have 30,000 lph at 2m head height, coming from a large Onga (aussie brand pool pump) magnetic drive pump.
<Mmm... I would use something else... you don't need the pressure this device produces, nor to pay for it>
I am going to order another smaller (23,000 lph)
<Again, I'd look into something with a different flow/pressure profile... see an outfit that sells pumps for other purposes than pools>
to see if this fixes the problem but in the meantime I am concerned about the broodstock I have already added to this system. How serious is gas-bubble disease for marine fish
<Very>
and what kind of exposure to micro-bubbles over what kind of period of time causes this?
<Just a small exposure in a period of minutes can be deadly>
Are can't seem to find a definitive answer. Even on your 'bubble trouble' FAQ's one person is told that micro-bubbles really are anything to be concerned about where another is told that they could kill your fish.
<Have seen the latter on a few occasions... There are papers written on the topic, gear devised to out-gas water...>
I can't see any obvious physical problems with my fish. The micro-bubbles seem to come out different returns depending on what I fiddle with and while it doesn't seem to bother some fish in others it seems to really disturb the fish, decreasing their appetite and causing them to withdraw into their tanks/decor.
Thanks in advance,
Ryan.
<Do look for "college level" general texts on aquaculture... both the issues of gas embolism/disease and aeration/gas saturation. Bob Fenner>

Re: Micro-bubbles/gas-bubble disease, ScottV, your input as well please re Pump sel., pb      2/17/08
Hello Bob, Thanks for your time, it's much appreciated. I have turned this system off for the moment and just added a few hang-ons filters/skimmers to the occupied tanks to keep them running and added smaller pumps to keep the systems filters alive. I know it wasn't an great idea to put fish in before I had all the kinks worked out but as some of my original tanks were originally in the area where the new system is now located I had to play 'musical tanks', setting the system up around the old tanks etc, moving broodstock into the new systems tanks while I plumbed and completed the system around it. So far only one fish (of course a wild-caught spawning black ocellaris female :() is still 'sulking' from this bubble problem, I'm hoping she improves, any advise on this front?
<Really, only time going by... unfortunately. Stable, optimized conditions... hope>
To be honest picking a pump for this system was the hardest thing I have had to do in that set-up. It's not something I have had personal experience with and was not something I had any luck researching in the usual places. The Onga pump I did purchase is one recommended by one of the biggest aquaculture companies in Aus and seemed comparable to a pump used in a similar system in a LFS I frequent.
<Mmm... much to state here. Perhaps the gist of what I'd like to made known is posted here: http://wetwebmedia.com/PondSubWebIndex/pdpumps.htm
and the Related FAQs link re above>
I am having a hard time understanding the difference between some of the flow rates of these large pumps, one persons 30,000 lph at 2m head height seems very different to someone else's, is the best way to compare them purely by the power consumption of a particular style of pump?
<Mmm, no my friend... Am wondering where we should start in this discussion. "Power curves" are available for most all pumps... But generally just knowing the approximate volume of flow at a given/stated total dynamic head suffices... My concerns are that you get good value in terms of what pressure you really need (likely little, and are paying a premium for much higher pressure) along with the usual need for chemical inactivity, long-life/service... The higher pressure coefficient too often figures into induced air-entraining issues (e.g. microbubbles) as well... Do read the above citation... and we'll chat further>
Would something like a ReeFlo Hammerhead pump of 335w rated at 22,040 lph at 0 head height be more what I am looking for, that brand is the only one I found reasonable info on but I thought they size was too small.
<Mmm, for what application/s?>
The system is set-up on two levels with the top level being around 7ft off the ground and the bottom about 3ft. I am using 40mm pipe for the incoming lines and 25mm-50mm for the of the outgoing. Other pumps available to me are the Lifeguard Seahorse's, RK2's,
<Ahhh! These I am very familiar with... re-packaged Baldor's... from some friends/associates from many years back... I do strongly encourage your looking into this line. VERY reliable, quiet, energy-efficient (this last is extremely important)>
and LINK's, none of which I was able to find much info on, if any. I had hope to put a reasonable amount of flow through this system, I plumbed it to take it
<Mmm, actually, some of the returns/drains, at 25mm, are not all that large>
but even in a system like this is it better to follow the general rule of reef tanks and have the majority of the flow in the tank coming from internal pumps and the like?
<Mmm, no... definitely not. Commercial concerns almost never rely on these secondary systems>
Thanks again for the help, I was so tempted to ask a few of these questions while I was doing this but they seemed like things I should have known.
<An excellent idea to check ones assumptions/understandings with others of similar background, interest... who can/will help. I do hope our Scott Vallembois will chime in here, as he and Eric Russell are most up to date in terms of these issues>
On another note, I'm not sure if you remember but a while ago I sent some pics of my Mccullochi Clownfish to include in the clownfish section,
<Ah, yes>
I think you replied at the time. Since then I have had some small success and raised some offspring, if pictures of the first tank-bred Mccullochi's are of any interest I would be happy to send a few over.
<Thank you for this kind offer. Unfortunately, due to so much travel, I only keep freshwater nowadays>
I could also replace the original pic with a nicer one with a nice anemone backdrop:), I sent a couple of examples, maybe not the best ID shots but a couple of my personal favourites. Kind Regards, Ryan Dwyer.
<Am going to run this as our pic of the day. Cheers, Bob Fenner>

Re: Micro-bubbles/gas-bubble disease, ScottV, your input as well please re Pump sel., pb 2/17/08
Hello Bob, Thanks for your time, it's much appreciated. I have turned this system off for the moment and just added a few hang-ons filters/skimmers to the occupied tanks to keep them running and added smaller pumps to keep the systems filters alive. I know it wasn't an great idea to put fish in before I had all the kinks worked out but as some of my original tanks were originally in the area where the new system is now located I had to play 'musical tanks', setting the system up around the old tanks etc, moving broodstock into the new systems tanks while I plumbed and completed the system around it. So far only one fish (of course a wild-caught spawning black ocellaris female :() is still 'sulking' from this bubble problem, I'm hoping she improves, any advise on this front?
<Really, only time going by... unfortunately. Stable, optimized conditions... hope>
To be honest picking a pump for this system was the hardest thing I have had to do in that set-up. It's not something I have had personal experience with and was not something I had any luck researching in the usual places. The Onga pump I did purchase is one recommended by one of the biggest aquaculture companies in Aus and seemed comparable to a pump used in a similar system in a LFS I frequent.
<Mmm... much to state here. Perhaps the gist of what I'd like to made known is posted here: http://wetwebmedia.com/PondSubWebIndex/pdpumps.htm
and the Related FAQs link re above>
<<This pump can work, but is unnecessarily expensive to run. I have walked into many the LFS that could save upwards of $400+ per month in my estimation solely by choosing different pump than the use.>>
I am having a hard time understanding the difference between some of the flow rates of these large pumps, one persons 30,000 lph at 2m head height seems very different to someone else's, is the best way to compare them purely by the power consumption of a particular style of pump?
<Mmm, no my friend... Am wondering where we should start in this discussion. "Power curves" are available for most all pumps... But generally just knowing the approximate volume of flow at a given/stated total dynamic head suffices... My concerns are that you get good value in terms of what pressure you really need (likely little, and are paying a premium for much higher pressure) along with the usual need for chemical inactivity, long-life/service... The higher pressure coefficient too often figures into induced air-entraining issues (e.g. microbubbles) as well... Do read the above citation... and we'll chat further>
<<I have added a few links with examples of the flow charts mentioned at the end of this correspondence.>>
Would something like a ReeFlo Hammerhead pump of 335w rated at 22,040 lph at 0 head height be more what I am looking for, that brand is the only one I found reasonable info on but I thought they size was too small.
<Mmm, for what application/s?>
<<I would encourage you to invest in two smaller pumps for redundancy’s sake. If one goes out you will still have one up and running while it is repaired. You will also likely manage to get more flow for less power consumed this way.>>
The system is set-up on two levels with the top level being around 7ft off the ground and the bottom about 3ft. I am using 40mm pipe for the incoming lines and 25mm-50mm for the of the outgoing. Other pumps available to me are the Lifeguard Seahorse's, RK2's,
<Ahhh! These I am very familiar with... re-packaged Baldor's... from some friends/associates from many years back... I do strongly encourage your looking into this line. VERY reliable, quiet, energy-efficient (this last is extremely important)>
<<The Baldor based pumps are hands down my favorite for high flow vs. power input (very quiet and reliable to boot). Also consider looking at the Dolphin line of pumps, they do offer a great variety of flow biased pumps. Keep in mind what you have going on is not what would be considered a high pressure application from a pump’s point of view. You will want to look toward the more flow biased offerings rather than pressure biased. As Bob stated, you will just waste power and money using the pressure rated versions here.>>
and LINK's, none of which I was able to find much info on, if any. I had hope to put a reasonable amount of flow through this system, I plumbed it to take it
<Mmm, actually, some of the returns/drains, at 25mm, are not all that large>
<<A 25mm (inner diameter) drain will only accommodate around 1150 lph safely. The larger 50mm up to about 4600 lph, there is a huge difference. You will want to cut your cumulative flow down to about 12000 lph or drill more/larger drains.>>
but even in a system like this is it better to follow the general rule of reef tanks and have the majority of the flow in the tank coming from internal pumps and the like?
<Mmm, no... definitely not. Commercial concerns almost never rely on these secondary systems>
<<This brings my attention back to where all this flow is being processed. How large is your sump/filtration tank? Regardless of how much flow you run through it you should be able to set it up to not return micro bubbles to your tanks. If it is simply too small to disperse the bubbles, cutting the flow back roughly 25% will likely not do the trick. You may need a larger sump area or need to rework whatever you have to keep bubbles out of your return. Something as simple as a filter sock over the drain lines can work wonders in getting these bubbles out. Also be sure that the end of each line is submerged, if it is draining into the sump above the water level it is just adding to the problem. Also be sure that all your plumbing connections are actually watertight. A return can appear watertight (not leaking) because it is actually introducing air into the line rather than leaking water out of it. The closer to the pump, the more likely this scenario is to be playing out, at the pvc/pump joint in particular. Do also be sure that any pump’s intake is unrestricted. If you need to control flow from the pump, do so from the output end.>>
Thanks again for the help, I was so tempted to ask a few of these questions while I was doing this but they seemed like things I should have known.
<An excellent idea to check ones assumptions/understandings with others of similar background, interest... who can/will help. I do hope our Scott Vallembois will chime in here, as he and Eric Russell are most up to date in terms of these issues>
On another note, I'm not sure if you remember but a while ago I sent some pics of my Mccullochi Clownfish to include in the clownfish section,
<Ah, yes>
I think you replied at the time. Since then I have had some small success and raised some offspring, if pictures of the first tank-bred Mccullochi's are of any interest I would be happy to send a few over.
<Thank you for this kind offer. Unfortunately, due to so much travel, I only keep freshwater nowadays>
I could also replace the original pic with a nicer one with a nice anemone backdrop:), I sent a couple of examples, maybe not the best ID shots but a couple of my personal favourites. Kind Regards, Ryan Dwyer.
<Am going to run this as our pic of the day. Cheers, Bob Fenner>
<<I hope this helps out, the links below should help also, there is much good information regarding pump flow and how to choose/apply on the Reeflo site in particular. The RK2 offerings are very similar to these. Good luck, Scott V.>><Thank you Scott. RMF<
http://www.reeflopumps.com/flowbiasedpumps.html
http://www.azponds.com/new%20sequence.htm#Dolphin
http://www.reefaquarium.com.au/index.php?p=productMore&iProduct=112

Re: Micro-bubbles/gas-bubble disease/Pumps and Plumbing 2/18/08
Hello Bob, Scott,
<Scott with you again.>
Thank you both for your help, and your quick response, it’s not every day you get two experts helping you out.
<Very welcome Ryan.>
My black ocellaris female I mentioned seems to becoming more outgoing but still hasn’t got her appetite back, I’m just hoping an unrelated problem isn’t the cause of this behavior and that I should be treating her with something.
<It does sound as though she is improving, give it time.>
Out of my options for pumps it seems as though the RK2 range seems the best one, it’s just trying to work out which one is the best for this situation.
<OK, these are good pumps.>
I should have been more detailed in my description on my system but felt like my reply was too long as it was. When I said my outgoing plumbing is 25-50mm I meant that it came out of 25mm bulkheads into 50mm pipes, as seen in pic 1.
<I see, in this case it appears you will be limited by the cumulative flow in the 50mm.>
This pic shows one side of the system, the 6 other 55g tanks run along the wall to the left. One thing I am going to change to the plumbing in that pic is to add a ‘breather’ to each side which can apparently help with my issues.
<It will prevent the drain lines from siphoning. I would also drill put a siphon break on each individual drain. Looking at your setup it would be easy enough to drill through the top of each screen just tight enough for a small piece of tubing. Run that 3-4” down (you may need to slide it up and down to find just the right spot) into the drain line and it will break the siphon in the line. This is not necessary at low flows through the drains, your setup will aspirate itself to some extent since the drains are exposed to the atmosphere.>
The incoming pipes run in a similar way, through 40mm then to 25mm with a ball valve on each tank to regulate the flow. I had also plumbed a couple of lines to supply a couple of bio-ball chambers in the sump, a DSB and an extra output to bleed any extra flow back to the sump if the flow was too much.
<OK>
My sump was originally 6ft by 3ft in size; its main draw-back was it was only 14 inches high. I had a real hard time tracking down anything in the dimensions I was looking for. I had a spare 6ft by 2ft tank and I kind of wish I had used that now, but it was a little too tall for my liking. I am going to be setting up a number of systems like this one (once I get this one working well) and for them I think I’ll have to get something custom made, just wish I had been patient enough to do that for this system. When I started to suspect the size of the sump was the cause of my bubble problems I plumbed another 3ft by 2ft by 20inches tall tub into the 6ft one and ran my outgoing plumbing through this first, to hopefully baffle the problem. Each line running into the sump is submerged. I do have a lot of pre-filter baffling the flow but if I still see bubbles after downsizing the pump I’ll try and attach filter socks. I originally was a little concerned about trying to block so much force directly. With both of the tubs joined together is this still considered on the small size for the amount of flow?
<No, we are dealing with a fair amount of flow, but the bubbles should be able to be dispersed over this run through the sump. I would skip the filter socks, bad communication on my part. I threw that out there as a fix for most home aquarists. In your case I would consider something mechanical such as foam on the return end of your sump to catch any bubbles that make it through the run of the sump. Of course a thorough bubble trap towards the return end helps too!>
One of the first things I tried to do to solve the problem was to find a possible air holes drawing water into the incoming lines, concentrating around the pump. I very carefully plumbed the incoming lines with high pressure pvc glue so I couldn’t see how any air could get sucked in around such a seal so I suspected the pump itself, or the bulkhead from the sump where this glue wasn’t used. From what I could tell this wasn’t the problem, I even sealed these fittings with silicone and saw no difference.
<All are possible causes and were worth mentioning, it sounds like we are on the same page.>
With all this in mind would you think a RK2 2120 (23,100 lph) would be too powerful?
<No, not when head pressure/plumbing runs are accounted for. These pumps also do well with throttling back if need be (on the output side); they will even use a little less power this way.>
Is the RK2 214C (13,500) a better option? Any other major problems with my design?
<Do drill the siphon breaks/install the “breathers’’ . This will help your situation. You may also consider replumbing the drains. The way the four tanks appear to be configured in the picture you are going to be limited to 4600lph through them, the flow capacity of the 50mm line gravity fed, likely less with the run and fittings. You will want either a larger line to combine the drains coming off the tanks into or limit each 50mm line to input from four 25mm drains. This will double the flow capacity in these four tanks, follow the same principles in the other six.>
Thanks again for your help.
Kind Regards
Ryan Dwyer.
<Welcome, do keep us posted on how things go, Scott V.>

Re: Micro-bubbles/gas-bubble disease/Pumps and Plumbing 2/20/08
Hi Scott,
<Hello again Ryan.>
Things seem to be improving here. My female black ocellaris is now eating hungrily again, which I am very happy about. I got extremely lucky getting a wild-caught black ocellaris pair in the first place and I certainly can’t replace them. This has seemed to have put this pair off spawning, but at least they are alive.
<Great to hear the situation has improved.>
Thanks for your input on my system design, I was concerned I may have made some major stuff ups but it seems I didn’t do too badly. Makes it much easier to plan for my future set-ups with your advice on board. I have added one ‘breather’ to each arm/stand of the system, should I have added one to each side of each arm/stand?
<You will want to aspirate the line in some way anywhere the gravity fed lines travel down any significant amount to keep the system draining consistently.>
This has improved things considerably, I started the system back-up just to see what difference it made and for the first day I got minimal bubbles, like what you would see if you added a new hang-on skimmer to a tank. Today after running for a day the amount of bubbles are increasing, I think it must be an accumulative affect. I have ordered the RK2 23,100 so I am figuring with this drop in flow I should see the last of these nasty bubbles.
<Can you throttle your current pump back to test this first?>
Thanks for the advice on the siphon breaks, I saw it mentioned in the faq’s and tried to just cable tie the hose to the side of the screen, you way works a lot better. I think I might have to re-plumb the drains, I am getting a bit of water bubbling up through the bottom standpipes if the total flow through that line is too great. I’m not sure if I should wait to see how the new pump goes, or just re-plumb it while I swap the pumps over.
<Either way, replumbing is not the most fun thing in the world, but at least it is not too difficult.>
Thanks again for your input.
Kind Regards,
Ryan Dwyer.
<Welcome, do let us know how it all sorts out, Scott V.>
Re: Micro-bubbles/gas-bubble disease/Pumps and Plumbing... and some C. tricinctus pix  3/15/08
Hi Scott, Sorry for the slow reply, my bubble problem has only completely cleared in the last couple of days.
<Great! I must apologize for my slow response also, it has been one of those weeks.>
Once I added the new RK2 pump things immediately improved. Bubbles reduced to practically nothing, and the noise was cut in half.
<Yes, the typical story with these pumps.>
Like last time when I added the breather's some bubbles did come back after a few days, and the same happened after adding the new pump. There weren't a lot of bubbles and I believed they weren't at dangerous levels. Over the last couple of weeks I have fiddled with a few things with little change. It wasn't until I re-arranged the area around the intake of the pump that I found my problem. A couple of bio-balls had somehow gotten lose and got stuck in the intake pipe.
<That will sure make a difference.>
Once removed, flow increased, and the bubbles stopped (insert big sigh of relief).
<Yes.>
In rare good timing, since I did this a few days ago my black Ocellaris pair I had been concerned about has laid another nest. So it seems I got through this with no great issues.
<Awesome!>
As I was writing this I remembered that I was going to try and take some pics of my Chaetodon tricinctus for your Unknown Chaetodons page. I recently moved my Tricinctus Butterfly into a different tank and am able to get some better shots of him so I thought I would include a couple with this e-mail. I left them their original size, so you can reduce them the way you like.
<Thank you, these will be passed along to Bob.>
Thanks again for your advice. Kind Regards, Ryan Dwyer
<Ryan, thank you for updating us on your situation, I am glad to hear it all worked out well. Welcome, have fun, Scott V.>

Very nice. RMF

Vortex XL Diatom Filter, op., bubbles  – 1/28/08
I have a Vortex XL diatom filter which I use weekly to polish the water in my 75 gallon freshwater tank. Sometimes the filter pumps out masses of very fine bubbles into the tank. The bubbles don't appear to interfere with the quality of the filtering operation. At times the bubbles are intermittent, and at other times are produced steadily. Is this normal? If not, any recommendation on how to eliminate the production of the bubbles?
Mike C.
<Yes... there is some place where air is being entrained here... Likely at either of the too-simple attachment points for the tubing going to/from the pump unit (the black nipples)... Either get/use new bands here, replace the tubing, and/or "lube up" a bit with some Silicone based material to prevent air from being pulled in. Bob Fenner>

Air bubbles, SW...  - 1/24/08
Hi WWM Crew,
<Paul>
Thank You for this site. It has saved me many times and put my mind at ease during times of panic. (Which have mostly been unnecessary). I hope to make this a short and quick email.
<Pleasure, made all the more easier by well crafted and accurate emails such as yours so Thank you. Now lets see…>
My problem is air bubbles. I have searched the site regarding air bubbles but haven't found quite what I am looking for. I have a 55g (1.5 years old) with a 29g sump and a 29g refugium (currently disconnected). To make it short the whole set up wasn't working. I was pumping out of the display into the uphill sump and refugium. I was having worries about overflow and the return getting plugged etc.
<Shouldn’t be a worry and should be simple to implement with a little planning and “fail-safeing” >
In the end I had to dismantle the sump and fuge (I know it was a mistake but I had no choice) and go back to the way the tank was originally set up - Hang on. Aqua C Remora Pro and a canister filter for activated carbon. The problem was that I had a massive outbreak of hair algae and Valonia before the dismantling. I have been fighting it for months with water changes, etc. I use RO/DI water and the TDS meter shows 0. I removed half (30lbs) of the LR and scrubbed it and I then put it in the sump and refugium because I had the room. I got rid of the algae problem for a while but when I dismantled the fuge and sump I returned all of the LR back to the display. No Valonia but the hair algae is back in full force. Here is my question. I now have air bubbles all over the glass and the LR when I come home from work. Not micro bubbles but big bubbles. I blow the glass with a turkey baster as well as the LR to get rid of detritus but the bubbles keep coming back. Is this a photosynthetic reaction to the hair algae? Is it because I removed the LR, which sat under no lighting for weeks? Did I kill part of the LR and this is some cycling reoccurring? I have leathers and zoo's and a small hammer coral with 5 fish. They all seem fine. I detect no nitrites or nitrates when testing. I haven't tested for phosphates but that seems to be the obvious answer for the hair algae. I want to make sure these bubbles will eventually go away. I am ready with water changes if necessary. I have a tub full in case of emergency water changes. Thanks for all of your help.
<Water changes are always helpful and if done slowly and methodically then should go a long way to addressing the problem. The bubbles are probably a combination of oxygen given off as you say, from photosynthesis occurring in the algae cells. Also the previously high levels of nutrients that fuelled your algae outbreak are probably locked up in the rock and now it is leaching back into the water and as it is being de-nitrified back into N2 (nitrogen gas) it is appearing from the rocks as bubbles. I would continue to monitor and this should stop once levels in the water and rock have reached equilibrium. Water changes, PO4 remover and careful diligence are the best things you can do right now. Hope this helps>
Paul
<Olly>

Aqua C Urchin troubles 12/18/07
Let me thank you first for being a great source of info. But let me get right into my problem. I have a 65gal moderately stocked coral tank with a few small fish, 50# LR and a 20gal sump. After going through your site and the rave reviews I bought an Aqua C Urchin Pro with the Mag3.
<Yes, nice skimmer.>
The tank has been setup for about 2 years and the skimmer was installed about 2 months ago. The problem I am having is even with an under/over/under bubble trap in my sump, the tank is constantly being flooded with micro bubbles from the skimmer. I do not add any additives such as stress coat, and I rarely put my hands in the water. The sump is plumbed with sch 40 pvc. The sump flows about 400gph. I spoke with Steve at Aqua C, and he said it is normal for this to happen. It is very unsightly to see this in a show tank. Any suggestions? Thank you in advance for your help.
<A simple piece of filtration foam cut to fit between the baffles (I would put it where the water comes over and back under) will keep most, if not all, bubbles from reaching your display. Welcome, good luck, Scott V.>
Nitrate: undetectable
pH: 8.1
Ammonia: undetectable
Phosphate: undetectable
SG: 1.025
Calcium: 480
Alkalinity: 3 <meq/L I assume.>
Temp: 82 day/78 night

HELP.... refugium looks like a bubble bath 11/26/07
Hello again,
<Hello Bill>
I had this refugium built by a local guy who builds tanks and also services them.
Looking at the pictures I sent you, my 1st question to you is: Why is the sock completely
under water? Shouldn't it be sitting on that bracket like most wet/dry systems?
<Not really, the sock should be somewhat submerged. It looks as though the bracket was built into the sump rather than needing to hang one off the side.>
Is there a design flaw here? Shouldn't there be another baffle so that the water level isn't so
high where the sock is?
<The second baffle from the sock would have to be cut lower to lower the water level here (unless there is an even higher baffle on the return pump chamber). From the pictures it looks like you could lower another inch or so. It looks like the sump was designed this way to give you as much volume as possible in the middle chamber, is this intended for a refugium?>
And why is it bubbling so much? Took the sock off and it's even worse...
<Is your overflow input on the sump under the water level? If it is not and it is constantly splashing that will explain the foam on top and why it would get worse with the sock removed.>
The tank is a 300 gallon circular tank, the refugium is 72"x 20"x 20" and I'm using an Iwaki 100.
There is also a closed looped mechanical filter using a Sequence 1/3 hp pump. Do you think the water flow is too high?
<No.>
Also, I'm getting micro bubbles in the return line, I can actually  see it getting spit out into the tank even though I barely see any micro bubbles in the water after the  last baffle/sponge. Could it be the loc-line fittings that I'm using? But the entire loc-line assembly is under  water and all my plumbing is pvc or flexible pvc and most of them are glued except where the Iwaki pump.
Thanks,
Bill
<I would first look to the pvc connections as the source, especially any joint with flexible pvc. The flexible can be tough to join, make sure you used a glue specifically for flexible pvc. You may want to actually silicone (make sure no mildewcides) the threads leading to the pump and let it cure 24 hours. This will assure a good seal here. Also make sure your pump intake is not restricted. Welcome, good luck, Scott V.>

Curious Pump Issue – 11/22/07
Hello All,
<<Greetings Jackie>>
I hope you and your families have a wonderful Thanksgiving.
<<Thank you>>
I have a question related to my return pump which is a Mag Drive 9.5.
<<Okay>>
The pump has been in use for approximately 1 year. A couple of days ago I noticed it is expelling a large amount of tiny bubbles into my main tank. Do you know what would cause this to happen?
<<Mmm, I’ve used this brand of pump for many years with good reliability (though I recently made a switch to the Ocean Runner line of pumps for some applications)…if the pump is “submerged” this is likely due to air intrusion somewhere along the plumbing line, rather than any particular fault in the pump itself. A joint/junction somewhere may have worked loose and is “sucking air” much like a venturi functions (only takes a very small pin-hole). It will take a bit of investigative work on your part to find the fault. One tactic for finding the air leak is to smear a bit of silicone grease around each joint “one-at-a-time” to see if the bubbles stop>>
Also, should I be concerned about the health of my inhabitants?
<<In my experience, unless the bubbles are very small and very profuse they are likely more of a nuisance to you, than anything else>>
Thanks,
Jackie
<<Happy to assist. EricR>>

Tiny Bubbles, No Wine 10/31/07
Hi Robert,
<Hi Josh, James today for Bob.>
I love your book, The Conscientious Marine Aquarist. Most valuable.
<Bob thanks you for this.>
I have read thru the posts on ?micro? and ?tiny? bubbles.
My question has to do with the ?flow rate? and what this has to do with generating those tiny bubbles.
I have a 70 gallon Oceanic tank with a built in overflow. It came with a Megaflow overflow. This appears to be their version of a Durso. (correct me if I am wrong, please).
The connection off the overflow feeding the sump is the supplied 1" hose that looks like a vacuum hose. The return to the tank is ¾? tubing. I have valves on both line that are Teflon taped. I don't believe that there are any air leaks. Can you explain to me why these tanks are plumbed with two different size pipes?
<The larger hose is gravity feed to the tank, no pressure forcing the water to the sump is used, whereas the 3/4" line is pressure fed and a larger volume of water can be pumped through the hose in this regard.>
I have wrestled the setup to control the gurgling noises. I want to increase the flow rate but at some point of opening the valve(s) I start to get those pesky microbubbles.
Am I to assume that the point short of those bubbles is optimal? That would be about ¾ open on my valves. I thought that I would be able to max out the ¾? return and adjust the 1"? inlet. In reality I have found this won't work due to the noise and the bubbles it creates.
Most importantly Can you explain where/how the bubbles are generated from?
Why do they start to form when I open the valves past a certain point?
<Based on what you are telling me, I'm thinking that when you open the 3/4" return line past 3/4, your pump is pumping out water faster than it is coming in. If the water level in the sump gets low enough, the intake will suck surface air into the lines thus creating the micro-bubbles. The term for this is called cavitation.>
Thank you for your help.
<You're welcome. James (Salty Dog)>
Josh

Protein Skimmer and stress? Adding a Skimmer 8/7/07
Hello from Tennessee WWM crew!
<Hello>
I have a two year old system (36g) and have finally bought a protein skimmer (AquaC remora)!
<I think you will be happy with this unit.>
I connected it to my tank today and of course I have some microbubbles. However my fishes seem to be freaking out and hiding. Will this stress them out and cause a death?
<Doubtful, they will get use to it.>
If so, what do you think should be done?
<Nothing, give them a little time.>
My other question is....probably an obvious no but...Can I alternate the skimmer between that tank and my 125g? The specs are for 20-80 gallons for the skimmer but hopefully you will grant me permission to alternate them???
<You could, although it will be underpowered for the 125, but I'm not sure why you would want to. Really both tanks would benefit from their own full time skimmer.>
<Chris>

I have a micro-bubble problem that just won't quit and wonder if you can help. – 07/03/07
Hi Crew!
I have a 125 gallon AGA tank with dual overflows that is piped to a 100 gallon
sump/refugium behind the wall its sitting in front of.
I am using two Genx pcx70 pumps.
One pump line goes directly; back to the tank.
One has a tee to feed the refugium.
The strange thing here is only one side has the bubble problem.
<A plumbing leak...>
My right side return looks great, the left side looks awful.
So I think this rules out the problem being in the sump.
I checked all the connections to the Left side and can't find any leaks.
<There is at least one there somewhere>
I pulled out the return pipe and cleaned all the loc-line fittings.
I noticed at one point when fooling with the loc-line that the bubbles stopped temporarily.
Do you have any ideas?
I was wondering if maybe the loc-line pieces could suck in air and maybe they need to be replaced?
<Yes... or at least switched with the other side to confirm the source of the leak...>
Thank you for any help you can give me.
Great site, I use it all the time.
David Matza
<Try switching out the Loc fittings... replacing the hard plumbing in turn if this doesn't disclose the source of entrained air. Bob Fenner>

Micro bubbles from my protein skimmer... Chemical Algicide use...   6/30/07
Good evening, all.
<Yawnnnn! AM here now>
I have a 100 gallon, fish only tank with about 50 pounds of live rock.
<Okay>
I turned off my protein skimmer on Thursday afternoon to treat a red slime algae problem in my tank. I used ChemiClean.
<... not advised...>
I've just turned my protein skimmer back on after being unplugged for 36 hours and it is producing an exorbitant amount of micro-bubbles that are getting pushed up into the tank.
<Good... you need to remove as much of the products, by-products of using this "algicide" as quickly as possible>
I've unplugged the skimmer to stop the micro-bubble flow for now, but I have no idea why the skimmer is causing them, or what else I can do to prevent it.
Any suggestions?
Trapped in bubbles,
Scott
<The Boyd product Scott... not a good idea... I'd do a few largish water changes... one a day over the next few days... leave the skimmer going, place some Polyfilter, Activated Carbon... and hope your system doesn't crash... Please read here: http://www.wetwebmedia.com/maralgcidefaqs.htm
and the linked files above. Bob Fenner>

Protein skimmers & bubbles in my new tank   4/15/07
What is the correct way to set it all up?
<Mmm, depends on the make/model...>
Will a lot of bubbles hurt my fish?
<Could, yes... see the term "emphysematosis" on WWM, elsewhere>
My nephew bought a set up like the tank (it's a ten gallon saltwater tank)
<Hard to keep such small volumes stable enough...>
, from the movie finding Nemo and doesn't know anything about fish, neither do I so here I am trying to keep my new fish healthy. thank you in advance for your help.......   
<Mmm... much more to relate... that is... related... I encourage you to choose to either "get involved" sufficiently to be successful here... or make this an easier freshwater system... Give it to someone who... Perhaps a book... at least a cursory reading of WWM: http://wetwebmedia.com/marine/index.htm
Bob Fenner>

Over flow box: air bubbles break siphon  4/5/07
<Hi Brian, Mich with you today.>
Please help!
<Will try!>
I can't find any specific solution to the tiny bubbles which break my siphon.
<I think I may know what the problem is, but I have a couple of questions first.  Are you using a U tubes or do you have a continuous siphon overflow box?  Do you know where the air bubbles are coming from?  Do you know why you are getting air bubbles?  The attachment is not coming through.  Could you resend the photo?  It may be helpful in trouble shooting your problems.>
I've looked at the provided links for hours and have also done many of my own searches, and still nothing.  Thanks for your time,     
<Welcome!  -Mich>

Re: over flow box: air bubbles break siphon  - 04/05/07
Sorry I don't know how to resize the attachment.
<Still not getting the photo.  It is very strange.  The email is showing there is an attachment but there is no way to open the attachment.>
To answer your questions so you can answer mine.  
<A question for a question if you will...>
I am using a continuous overflow box.  
<I have used this also and I too experienced this problem>
The bubbles are created when the water first enters the overflow box from the aquarium only when the water level of the water reservoir of the overflow box is lower than the level 1 which I marked on my attachment.  While the water level of the reservoir box is kept higher than the level 1 mark, the bubbles are not created.  The problem is keeping the water level of the reservoir of the overflow box higher than the level 1 mark using my ball valve and without overflowing my aquarium.  I can usually get the water level of the reservoir to stay at the level 1 mark for about a day, and then it slowly decreases.  I'm not sure why it doesn't seem that many people have the same problem as me because when I l search for  "bubbles and overflow box" the problems others have are different.  Maybe I am doing something wrong. Well obviously not right!
<I think so. I'm not totally clear on how you have things set up, but I think I understand enough to offer some suggestions.  A couple of options.  You can get an "Air Lifter" pump and attach it via airline tubing to the knob.  This will continuously remove any air which gets stuck in the top of the overflow.  The pump sits on the top of the overflow and does not get submerged.  Or you can use a power head which has a venturi feature. Again connect it to the knob via airline tubing but the powerhead will need to be submerged in you tank.  Either of these will continuously remove any air build up and you should allow you to complete open you ball valve.  Does this make sense?  I have used the air lifter and have found them to last about a year.  I always kept a back up on hand.  When you start having a problem with circulation that you can't figure out, check the air lifter.  It might need to be replaced.  It may acts as if it is working, but I have found over time it looses suctioning ability.>
Thanks again for all the help,     
<Welcome! Hope this helps!  -Mich>

Re: over flow box: air bubbles break siphon  - 04/05/07
<Hello again Brian, Mich here.>
Awesome! You have cured my headache thank you.  
<You are most welcome!>
I did have a venturi powerhead so I tried to mess with it and couldn't figure out how to incorporate it with the overflow box, so I did a search online.  I came across a forum that said instead of using a venturi powerhead or an "air lifter" you can just attach airline tube to the top of the overflow box and start directly siphoning this to your sump/my refugium.  I did this and it works.  The air bubbles are forced to siphon down to my refugium.  I think this is great, but I'm wondering if this is safe (over fill proof).  As long as my tank is safe from loss of power, reverse siphoning from return pump line, and loss of siphoning from overflow box  It should be safe right?   Is there any concerns that you might have about this vs. the "air lifter" or venturi powerhead.  
<My biggest concern was the airline coming out of the sump and siphoning several gallons of water onto the floor.  Also complicating the matter for me, was airline tubing looks way too much like a kitty toy.  In my house this was way too tempting.  You may be OK if there are no four-legged critters or little two-legged ones!>   
Thanks again,   
<Welcome!  -Mich>
Brian

Air bubbles in plumbing discharge   2/22/07
Hello Bob,
I had a question for you regarding my 90 gallon reef aquarium. My return  for this tank is spitting air into the aquarium and I can't figure out where it  
is coming from, I have checked the plumbing to make sure its secure and not leaking, and the filters water level is not low. The tank dimensions are 48"x 18"x 24" the pump running the system is a blue line 40 HDX The tank sits about 4  feet in up on its stand and the sump is located below the tank on the floor.  The bubbles coming from the return are very tiny and there are tons  of them. Any suggestions on what to look for to fix this?
Thank  you,
Brian
<Almost assuredly there is a "pin-hole" leak somewhere... very likely in the discharge side... of your plumbing... You might get lucky and just detect this with a spray bottle of water, or systematically covering each solvented and threaded joint with a very wet paper towel... but if the tank has no livestock in it as yet... I myself might "skip ahead" and daub a bit of solvent over these areas... to seal up the leak where the air is being entrained. Going forward, do you use clear or purple primer before solventing? I would... and a smear of Silastic (rather than Teflon tape or pipe dope, or...) on all thread to thread connections... can/will "come off" if the need arises... Bob Fenner>

Thank you... Found! Source of air entrainment/bubbles, Not-Caulerpa control/biol.   2/23/07
Bob, thank you for the advice, I found out that the bulkhead to the return nozzle was the culprit for the air pouring into my tank!
No more air!!
<Ahh! Congrats!>
I also found a way to manage the algae problem I mentioned in a previous email. It   turned out to not be Caulerpa, but I am guessing hair algae, I didn't know hair algae could be feathery in appearance, but the Trochus, and Nerite snails, along  with the red tip "equal handed" hermit crabs I added seem to be really doing the  trick working as a team on it, I stocked the tank sparsely with them so they  would have enough to eat and hopefully wont run completely out of food. I will  be putting 10 Nassarius snails in the tank soon also. The Trochus snails  are really going at the diatoms in the aquarium as well, I have been seeing a  lot more coralline on the rocks. The tank does have animals in it now, three  crocea clams, the smallest 2 are three inches, and the larger is 3.5 inches.  There is a yellow tang, about 4.5" in body length, a coral beauty that is  about 2.5 inches in body length, a mandarin dragonet, a large six line wrasse, a yasha haze (white ray) shrimp goby, a young Banggai cardinal  fish, and a group of squamipinnis Anthias 1 male, and 4 young females. I  also plan on getting a lineatus wrasse in a couple of  weeks. This is all in a 90 gallon reef, no corals yet, but it is looking to  be possible soon. The fish and clams have been in for almost a week now and no  signs of stress, illness, or anything to a negative effect. I check the water  every few days for calcium levels, dKH, PH, Nitrate, Nitrite, and  Ammonia, haven't had any readings on ammonia or nitrite since I set the  tank up, I cured all the live rock in dark vats before hand for 5 weeks with  vigorous water flow and protein skimming, and left lots of area for water flow  when I set up the aquascape. The readings have all been great, calcium just  above 420, dKH at a constant 12, PH at 8.3, Nitrates at 0, Phosphates  at 0. The temperature in the aquarium is 80 degrees F. around 12  PM to 8 or 9 PM then it slowly cools down later to no lower  than 76 degrees F.
<Mmmm, would raise the settings on your heater/s to about 78 F.... four degrees in a day can be a bit much>
  The tang still hasn't become fond of prepared  foods, but seems to prefer the algae growing in the aquarium, I feed the tank  small portions 3 times a day with Cyclop eeze, brine shrimp, krill, oyster eggs,  and blood worms. I use Kent's garlic extreme, and Selcon in their food. I also  use Kent's marine C. to boost their vitamin C. Thank you for your help, I really appreciate it, and my animals do too!
Thanks again,
Brian
<Thank you for this follow-up, insights. Bob Fenner>

More On Micro-bubbles And Their... "Origin?" - 02/12/07
Hello Crew,
<<Jeremy>>
I am having the same problems as the person of the post I copied below this one is having.
<<Ok>>
I have two sets of over-under baffles and also my flow into my refugium is going through a 200-micron filter sock.  I have a Mag-5 submersed for my return.  My return line is 3/4" and my bulkheads are threaded 1".  I have an adaptive nipple that is 1" female to 3/4" male.  Inside my overflow I have 1" hose going into a "t", 3/4" hose coming off of the "t" back into my tank.  All the hose is flexible clear hose.
<<Hmm...perhaps replumbing with hard-pipe will make a difference here>>
I feel that somehow my return hose is causing the bubbles, I can't see any bubbles entering my pump in my refugium.
<<This is not uncommon.  Even the smallest pin-hole leak can cause air to be drawn in to the return line>>
I also have the sponge that comes with the pump covering the inlet.  You say that this person's problem is air entrainment.
<<Sounds like it may be your issue as well>>
Could you explain this more to me?
<<Quite simple really...is the "inclusion of tiny air bubbles" and is most often described as relating to making concrete more "workable" without adding excess water.  But for our purposes, when speaking of air entrainment in the hobby/on these pages we are referring to air that becomes introduced/trapped in the water flow path.  This can be air that gets "gulped" down the water intake on the way to the sump...or it can be as already mentioned...air that is "drawn" in to the flow path as in a venturi, or a loose fitting, etc.>>
How does this happen?
<<It is often the result of faulty "joints" in the plumbing lines.  One way to avoid these is to use well cemented PVC pipe as much as possible to reduce the number of "clamped" joints or use "continuous" runs of flex pipe to eliminate joints altogether>>
I have seriously been losing sleep over this and my wife says if it is causing me so much stress she is going to make me sell the whole set up, and I have only had it running for one month!  Help!!
<<Try sealing the joints on the output side of the pump one-at-a-time (with silicone grease) until you find the offending joint/joints>>
Thanks,
Jeremy
<<Happy to share.  EricR>>
Micro bubbles in my tank   9/21/06
I have been going in circles with my 120 gallon tank for 5 months now to no avail. There are bubbles everywhere in my tank. Well first I spent 200
dollars on sump with baffles and visibly there are no bubbles in the pump chamber it looks completely clear. I am using a mag 9.5 submerged). The
return is made with flexible tubing split half way up with a tee to the return pipes.
<Likely air entrainment... very likely at one of these junctions...>
everything was working perfectly except for the bubbles. So I thought just the other day could the bubbles be coming from my pump. So I unplugged it
put it in the main display and there was the culprit bubbles coming out in short burst. so my question to you guys which have helped me so much
already. Is there a submersible pump with a 3/4 inch outlet that will not cause these problems because this is not the first time this has happened to me. Thank you.
<... how did bubbles come from a submersed pump? This is assuredly not the source... but one of the lines distal from the discharge. For one, I'd
replace the flexible tubing with solid... If you're set on using a submersible pump, you can... but they have downsides... Please read here:
http://www.wetwebmedia.com/ca/volume_3/cav3i1/Powerhead_test/powerhead_comp.htm
and the linked files at the bottom. RMF>

Belching Return Pump, Possible Air Leak   2/11/07
Hi Crew,
<Hi Jason, Mich with you tonight.>
I'm having a problem with my Quiet One 6000 return pump. Once every few minutes, it will spew a stream of bubbles into the display tank. This is preceded by a "shhhh" noise from the pump, like the sound of opening a soda.
<Sounds like an air leak.>
The pump is external, connected to the sump by about 14" of PVC plumbing as follows: (all 1") bulkhead -> threaded connector -> ball valve -> connector -> union -> pump. All slip connections are PVC bonded, and all of the threaded connections have silicone except the union->pump connector. The bulkhead intake is 12" below the water level of the sump, and it is not drawing air from the surface. On the return end, I have pump -> union -> connector -> ball valve ->
nipple -> vinyl tubing -> nipple -> elbow -> bulkhead.
<First place I'd check would be the vinyl tubing.>
Any thoughts on what is happening?
<Sounds like you're drawing air somewhere.>
My particular confusion comes from the intermittent nature of the problem... there's some sort of buildup followed by release of these bubbles from the pump. Would a simple loose connection or small air leak cause this?
<That would be my thought.  Have you tried checking for water leaks while the pump isn't running?  It may require the water to rest in the plumbing for a while before revealing itself.  The pumps may need to be turned off for more than a few minutes, maybe a hour or so.  Obviously make sure all the exposed plumbing is dry initially.>  
Thanks for any advice!
<Hope that helps!  -Mich>
Jason

Bubble question
Hello,
Thank you in advance for you help.
I have a 1" hose running into my refugium under my main display tank from my built in overflow.  The problem is that I am getting a lot of bubbles coming into my refugium from this hose.  I am using a stockman down pipe that I bought from his web site and I made sure that the hose is going down into my refugium at a gradual down sloping angle.  I have read on your web site to put in a "T" or "L" in the inlet hose somewhere to help reduce bubbles, is that right?
<Mmm, might... but I would add a "sock" here... as well. Look at the mighty fine ones offered by Emperor Aquatics...>
Could you explain to me where to put a "T" or "L" into the hose to help reduce bubbles.
<At the distal end... under water, in the refugium...>
   To help keep the bubbles from getting back into my tank I am using the filter foam that goes over the intake of the Mag 5 pump that I bought for my return,
<Good>
I also put a filter sock over the foam of the intake of the Mag 5 pump.
<Mmm... no, not a good idea... this is a centrifugal type pump... pushes... doesn't pull... need to have some screen on the intake side, but the real restriction should be on the discharge... the end>
  However I am still getting little bubbles into my main tank.  If there was a way I could limit the bubbles getting into my refugium I think this would help greatly.
Thank you very much.
Jeremy
<Please read here: http://wetwebmedia.com/bubtroubfaqs.htm
and the linked files above. RMF>

Re: Colt Coral and new question re bubbles    1/17/06
Thank you for your prompt response to my question.
<Prev. corr.?>
  My colt coral  opened back up today and seems to be okay (he is not back to normal size  yet).  I also moved the cabbage to give him a little more current.
<Good>
   When I woke up this morning he had a clear slime releasing from his middle but  as the day went on he opened up and seemed okay. I am now having another problem  and after researching most of the day on the Internet I have not made a  conclusion. I am having a problem with tiny bubbles in my tank.  I have a  30 gallon tank with what was about 3 inches of live sand all the way  around.  Now I have hardly any sand under my live rock and mounds in the  front thanks to my 2 engineer gobies.
I have noticed some bubbles covering the  corners of my tank and some of the rock.  I thought it was my protein  skimmer at first because I can not seem to get it tweaked.  However,  I  turned the skimmer off yesterday and the bubbles are still appearing  even after I fan the water to release them.  I added 5 Nassarius and 3  Cerith snails about a week ago could they be causing a release?
<Mmm... might re related... but not for sure>
I have had  this tank set up for about five or six years now and did move it to my  new home over a year ago with no problems.  I read some articles today  on old tank syndrome what are your thought on that?
<Does occur>
  I also did a  water change a week and a half ago and again today about 25%.  Also  the new light with the two 96 watts dual bulbs was added a week ago.   Thank you for your help ahead of time.
Tiaa  
<More likely an effect of the new lighting... boosted photosynthesis in these areas... gas accumulation... I would re-direct your circulation toward the corners and not worry at this point. Bob Fenner>

Bubbles in Main Tank, cavitation? 1/13/07
<Ken, Graham T. with you tonight.>
I have a 180 gallon tank plumbed into the basement which dumps into a 300 gallon sump.
<Big sump. Good.>
The return line is 2" pvc to a hammerhead pump which pumps a head of about 12' in 1.5" pvc to the tank. I am circulating about 3,500 gallons per hour from the sump.
<I only see one hammerhead pump with a 2"inlet and 1.5" outlet, and it isn't rated for that head... but I probably missed the one you have.>
I also have a closed loop moving additional water within the tank with four returns. My issue is that I am having tiny bubbles returning from the sump to the main tank. The sump is very calm , tiny bubbles not visible and I have tried a return box with sponges to trap possible bubbles and multiple inlets to decrease the intake draw of water, nothing seems to decrease the bubbles. Can my powerful pump be chopping the water and creating air bubbles.
<That would be my guess. The large differences in pressure associated with pumping volume at that head with induce cavitation. Cavitation, simply put, is just water boiling because of the extreme low-pressure on the input side of your pump. Remember, it is not just heat that makes water boil, but pressure differential. Adding more lines to feed the tank will do little or nothing since the low pressure is found at the impeller-housing, after the 2" restriction. The real change must be made at the out-put stage. Unfortunately, if you do have the pump I spec'd out (Dart), then you may be undersized to boot. Either way, utilizing a low-speed pump, using multiple pumps, or enlarging the inlet-size of your current pump are all ways to reduce the unsightly bubbles you generate. HTH,
-Graham T.>
Thanks Ken

Solution - Turboflotor 1000 and bubbles in sump/tank
I was able to get rid of 90% of the bubbles. I "invented" a device. Maybe I should market it! Since my overflows use 1" PVC and output from Turboflotor are 5/8", I made a bubble trap with a 2" piece of PVC with cap on bottom. I made it about an inch higher than normal sump level. I then inserted this into a Marineland filter material (filter in outside). I then flow water from overflows and from skimmer into top of the PVC traps (overflow and skimmer returns extend about 2/3 of the way down into the traps). The water flows in, cascades out of top (which dissipates some bubbles) and then flows through filter material. The filter material removes most of the remaining bubbles. This has
eliminated 90% of the bubbles - the only one that remain are extremely fine and evidently pass through the filter material. There are still bubbles but they are greatly reduced. If I could find a finer filter material I am sure I would eliminate almost all of them (something like a sponge-type filter with a 2"-2.25" opening in middle to fit 2" PVC trap).
<Emperor Aquatics makes micron filter bags that maybe just what you are looking for. They are extremely efficient at trapping debris, but must be rinsed out almost daily, for fear of becoming a home for nitrifying bacteria.>
Will the remaining 10% bubbles and of very fine/smaller nature pose much of a danger now?
<Probably not much>
They are hard to see anymore and most evident under the 2 x 96 compact fluorescent lights. You can't see them coming out of the return anymore - before it looked tons of dust blowing out into the water. They are very very fine and smaller now and don't seem to stick to everything anymore. - Mark
<Do look at the micron bags as another option. If you clean them regularly, they are very effective at removing large amounts of detritus. -Steven Pro>

Protein Skimmers...Tiny Bubbles Do Not Make Me Happy 12/8/06
I'm hoping that someone there can help out with a question in regards to protein skimmers. I have an Aqua C Urchin Pro driven by a Mag 3 pump. When I turn it on it fills the top <of the> tank with micro bubbles within minutes. I have tried turning it on with different water levels in the sump, I tried all possible cup placements, no luck. I contacted Aqua C and went back and forth with them a few times and they feel it is something in the water.
<I tend to go along with them.  Some additives can/will cause this.  Have you used any additives recently?>
It's a 75 gal. tank with a 37 gal. sump. I moved the water from my 50 gal. tank into this setup and filled the remainder with saltwater that I mixed from an R/O.
The tank has been running for approximately 4 weeks. I can not run the skimmer because it fills the tank with micro bubbles.
<Ahh, did you put any Stress Coat or similar product in the water on initial set-up?>
At this point I would like to consider replacing the unit out of frustration. I have been on your site and have become very confused, some people swear by the ETSS, then others say it's too loud and cumbersome to clean because of the bio balls. Others say that Euro Reef with an Eheim motor and not the proprietary motor from the manufacturer is the way to go.
<All good skimmers, and the Euro Reef/Eheim combo is a good choice.  The Eheim pumps seem to last forever.  I like skimmers that offer the least amount of adjusting/tuning, etc.
I'm using a Tunze and find this skimmer to fall into that category very much.>
Based on what I have described can you offer any suggestions which would make this decision easier?
<I wouldn't throw the towel in yet.  Get yourself two units of Chemi-Pure and place in the sump where some water flow will go through the bags.  If there is anything in your tank that could cause the micro bubble problem, this will remove it.  I feel the Aqua C skimmers are a very good and hear very few complaints about them.>
Thank you very much in advance for your help,
<You're welcome.  James (Salty Dog)>
Ron Kennedy

Re: Protein Skimmers...Tiny Bubbles Do Not Make Me Happy 12/11/06
Sorry I just noticed a typo, I meant to say that I did use stress coat <Stress Coat> when I made up the water.
<This will definitely cause your bubble problem.>
On 12/8/06, Ron Kennedy wrote:
>> Thank you for the quick response, I did use Chemi pure <Chemi-Pure> when I made up the
> water. I actually have two new <units of> Chemi pures <Chemi-Pure> in the container. My sump is a 37
> gal. tank with a glass divider about two thirds of the way over, will it
> work if I get a specimen container drill holes in the bottom and hang it
> over the divider with the Chemi pure <Chemi-Pure> in it. Do <Does> the Chemi pure <Chemi-Pure> need to be
> fully submerged. Also, how long do you think it will take for the Chemi pure <Chemi-Pure>
> to work.
><Does need to be submerged or have water flowing through it.  The Chemi-Pure, depending on the flow rate through it, should take a couple days to remove the Stress Coat.  Please check your caps and grammar before sending so we do not have to do it.  Our time per day is very limited.>
> Thank you so much for your honesty!!!!!!!
><You're welcome.  James (Salty Dog)>

Air Bubbles in MegaFlow Return - 12/08/06
Hello,
<<Howdy>>
You have a great website!
<<Thank you>>
Q:  I bought a 95-Wave Aquarium from All-Glass Aquarium.  The system came with the All-Glass Aquariums MegaFlow Overflow Accessory Kit.  After I start the system everything is working fine but I noticed that the system was pumping small air bubbles into the tank.  After a while I realize that the "3/4" elbow" has a little hole that is placed on purpose.
<<To stop back-siphoning when the pump/power is off, yes>>
This small hole is an anti-siphon feature in the event of a power outage.
<<Ah...I should read ahead *grin*>>
When I close (using my finger) the little hole the bubbles will stop.
<<Try positioning the outlet pipe such that the "hole" is "just below" the surface of the water.  This should stop it from entraining air with the water stream>>
I have seen these systems working in other aquariums and it seems to work fine, (no air bubbles).
<<Likely the outflow pipe was positioned as I described>>
Can you help me realize what is wrong with the ¾ elbow?
<<Give my suggestion a try.  If it is not possible to position the "hole" below the water line, then block the hole and position the pipe outlet shallow enough that the sump can handle the transient water in the event of a power outage>>
Best regards,
Luis Miguel Ferrero
<<Cheers mate, Eric Russell>>

Re: Air Bubbles in MegaFlow Return - 12/11/06
Howdy Eric,
<<Hello Luis>>
I did what you recommended me and everything is working fine.
<<Ahh, very good to hear>>
Thanks!
<<You're quite welcome>>
Nevertheless, the weekend I reviewed other systems that utilize the same Overflow and notice that although the water level did not cover the small orifice it wasn't throwing air bubbles into the tank. (?)
<<Hmm...perhaps those systems are utilizing smaller pumps/less powerful flow...or maybe the holes were "plugged">>
Rgds.
Luis Miguel Ferrero
<<Cheers, EricR>>

Tiny Bubbles (In The Wine??) 11/23/06
Crew,
<Adam>   
Happy Thanksgiving to you all. Lets all take a second and think about the great things we are blessed with.....OK, lets go!
<Yes it was.  I was blessed with a very good paying job.>   
It's been awhile since my last major fiasco, but sure enough I am in a pickle again.
You are all the experts and with your advice I have defeated Ick, developed a quarantine system and have had excellent results with my tanks..... SO I UPGRADED!
I got a new house and a new 120 Gallon "all glass" Aquarium with 2 drilled in overflows that move 1200 GPH (all glass specs). I also have a clear pro wet/dry sump that is rated for a 120 gallon tank, so it is like 8 gallons (I KNOW I KNOW, my Local fish store was off the base recommending this one and I now regret it.) I also have a mag 7 return pump that is connected to flex tube into a T, then one goes to a 3/4 PVC return and the other side is 1/2 flex tube to a return water shooter deal (name??)
My problem is I am getting a undesirable amount of micro bubbles.
  1.My hypothesis is that my Mag7 is not flat in my sump it is sitting slanted due to not long enough flex tube. This may be causing this?
<Unlikely.  Are you seeing a water vortex just above the intake of the pump?  If so, your problem lies here, and a higher level of water
will need to be maintained in the sump.>
  2. My return GPH is too much for my sump?
<No, the Mag 7 is rated at 700gph at the nozzle, and with your "T" in the system, plus hose length, you are probably pumping closer to 600gph at most.>
  3. On my PVC return the elbow is a 90 and I didn't flex the return top that shoots the water into the fish tank?
<Would be better to put the "T" at the pump outlet and flex hose from there to your outlets, but would have nothing to do with the bubbles.>
  4. Instead of having a T return, should I have just 1 main return and fore-go the double return??!?
<I'd stay with the dual return.  If the pump is brand new, you will experience some micro bubbles until the plastic components get seasoned, but the bubbles should only appear occasionally.  If they are constant, you are sucking air somewhere in the intake.  Another point...Is the sump water bubble
free to start with?>   
I don't think my problem is a venturi type issue because 98% of the tubing is flex tube which couldn't have a hole or it would shoot water out like a cannon?
<It is the joints where the problem will lie.  Good idea to apply some Lifeguard or other brand of silicone grease on the fitting before putting the hose on to it,
and be sure it is clamped securely.>
Any other ideas from you would be appreciated. I cannot solve this mess and this is the first I have ever dealt with an overflow system and I am getting stressed out. I have read 5 hours worth of the info on here and I really would like a personalized answer.
I appreciate all you guys do and as soon as my tank gets up I am putting a advertisement for your site on it..
<Mmm, you are putting an advertisement on your tank??>
Thank you all!!!!
<You're welcome.  James (Salty Dog)>   
  -Adam

180 gallon tank ... bubble city  11/10/06
Bob, I have a 180gal with two corner overflows boxes with one 1 1/2 Durso drains in each one. My returns are 1." until you get to the 3/4 bulk heads in the bottom of the tank, I have one exit on each of the over flow boxes, so I have 2 - 3/4 outlets powered by a Turbo sea 1190. I have one Turbo Sea 780 with 3/4 return, which goes through my chiller and returns to my main tank via sea swirl. Both of these pumps draw water from my sump and return to my main tank. My sump is 34 X 20 X 16.  My problem is breaking down the micro bubbles from the 1 1/2 returns. I have one set of baffles, which may or may not be good enough for this high flow system.
<Apparently not>
I have put socks around each return still have micro bubbles,
<Good try... you may need a "foam" dissipation area...>
I have replumbed and triple checked each fitting no leaks. Do you have any suggestions. I have done just about everything to figure out if I have an air leak or is the return flow just to much.
<May just be the turbulence, mixing of water here... most likely... could add another sump area to receive water, or the media area alluded to above to allow coalescing>
Fortunately the tank has only been operational for about 5 months, have live rock, sand bottom , refugium (which is incorporated into my sump) and three fish. I don't want to go any further until I have solved the problem, by the way I have taken the skimmer out to eliminate that problem if there was one. If I take the micron bags of the returns, I have so many bubbles it is hard to see,
<Yes>
with micron bags on bubble situation is better, but still to
<too>
many bubbles for corals.
Any input would be greatly appreciated,
Thanks,
Frank
<Please read here: http://wetwebmedia.com/bubtroubfaqs.htm
and the linked file in the series above. Bob Fenner>

Small Bubbles from Sump Return Pipe – 11/01/06
Hi Eric,
<<Hey Ken>>
I have an annoying dilemma.
<<Uh-oh>>
Would you have an opinion as to what is causing small bubbles coming out of my return pipe into my tank?
<<Sure...I have opinions on most anything <grin>.  It is likely you either have a very small plumbing leak that is “sucking” air...or the return pump is pulling bubbles from somewhere in the sump>>
It has been like this since the first day.
<<A very common issue>>
I was told last week by someone that it was probably because it was new sea water in the tank.
<<...!?  I don’t think so>>
However it is still occurring.  As you know my tank is a 90-gallon AGA mega-flow tank which has the internal skimmer box.
<<Yes>>
I put saltwater in it 8 days ago.  6 days ago I added about 120 lbs of live rock.  I have a 48” MTC Beckett style skimmer coming off the other side of my sump which has two baffles.
<<Have you checked to ensure the baffles are keeping bubbles away from the return pump?>>
When I look closely at the return to tank side of the sump, I really don’t see any bubbles to speak of so I do not think that this is the reason.
<<Ah...ok>>
Also when I shut the pump off and turn it back on, a lot of large bubbles come out of the pipe going into the tank.
<<When the pump is off the return line drains, yes?  The “large bubbles” would be the air that is pushed back out the pipe when the pump is turned back on>>
Is there air in the system?
<<Possibly from a small (pinhole) leak at a connection/union>>
The water flow from my sump to my tank is as follows:
¾” pvc flex tubing into ¾” union >>> Blueline 40 pump >>> 3/4” flex tubing  >>> bushing to increase to 1”>>> 1” ball valve >>> 1” union >>>1” ball valve >>> Bushing to decrease to ¾” >>> ¾” PVC >>> two 90 degree ell’s into my chiller >>> two 90 degree ell’s from my chiller >>> ¾” flex PVC into the bottom of the tank for the return.
<<Lots of joints...you need to check each one of these (that is “out of water”) to determine if one is “leaking” air in to the system.  You can smear Vaseline around each joint, though this must be “cleaned carefully” to keep the petroleum component from deteriorating the plastic (Bob does not recommend this method), or you can get a silicone grease for doing this.  Seal each joint one at a time, waiting a few minutes each time to see if the bubbles stop>>
The other problem (and maybe related) is that when I put my hand in front of the return line into the tank, I hardly feel any flow.   The Blueline pump is rated at 790 gph @ 5’ head.  I used a head loss calculator and I should have at least 560 gph.
<<Did you also take in to account the turns/valves in the plumbing?  Each 90-degree ell adds a foot to the head height, and I would also add a foot for each ball valve in the line...the unions and the chiller will be adding some additional resistance to flow as well  All in all, you will likely find the pump is less adequate than you thought for this installation>>
I am not sure what that feels like against my hand, but it has to be more than what it seems.
<<Only way to know for sure is to direct the output in to a container of known capacity and time how long it takes to fill>>
I appreciate at any idea someone may have.
<<Hope I’ve given you a few>>
Thanks,
Ken
<<Regards, EricR>>

Re: Small Bubbles from Sump Return Pipe – 11/01/06
Hi Eric,
<<Hello Ken>>
Thanks for the quick reply.
<<Welcome>>
When I get home tonight I am going to shut-off the skimmer and see if that is the culprit or not.
<<cool>>
With regards to your other idea (pin hole leaks etc), I need to re-do some of the plumbing as I exchanged my chiller and I will have the new skimmer on Friday.  I think I will just re-do all the piping instead of playing detective.
<<Okay>>
Is there any problem with gluing PVC and then running the system with the live rock?  Any toxicity issues?
<<Give the solvent an hour to cure and you’ll be fine>>
I used a head-loss calculator when I came up with my numbers.
<<So you mentioned...>>
It asks how many feet vertical/horizontal.  Number of valves, unions, 90's, 45's, etc.  It also lists all of the pumps that are used.  Pretty neat calculator.
<<Sounds like it...if it is accurate <grin> >>
I guess I have to get out my 3 gallon bucket, and see how long it takes to fill, and then multiply by 20.
<<Mmm, not sure I follow...  I would time how long it takes to fill the bucket, divide that number in to 60 (minutes in an hour), and multiply that number by 3 (capacity of the bucket).  The result should be the GPH of the pump with the current plumbing configuration>>
By the way, I ended up with an H&S A150 - 2001.  I heard H&S is supposed to be good.
<<As have I.  I have seen this make of skimmer in action and it was impressive...it also looked to be well made/engineered>>
It is similar to the Deltec AP-600 but rated a little larger than the Deltec.  In your opinion do you think this should be more than enough for a 90 reef?
<<Should be more than adequate>>
Thanks,
Ken
<<Cheers, EricR>>

Major Micro-Bubbles in the Sump – 10/23/06
I have a micro-bubble problem that has kept me up late at night for the past two weeks trying to solve!  I have narrowed down my source of the bubbles to the water draining into my sump.
<<Not uncommon...often caused by trying to “maximize” flow>>
My system is a 215G aquarium which I purchased with just the factory drain holes.   I'm only trying to push about 700GPH combined through these holes with the use of two submersed Mag-Drive 7's.
<<I see, but how large are these throughputs...how many?  Have you “measured” the flow from the pumps or is this a guess?>>
My sump consists of two 30G Rubbermaid containers joined a few inches from the top by two bulkheads.  I have four other containers cut out at the bottoms and tops to act as baffles.  Water enters from the drains by two separate pipes (1 pipe for each overflow drain) and into the skimmer container on one side of the first 30G container, and exits by the pumps from the totally opposite end of the 2nd 30G container, this is a good 4 1/2 ft of travel.
<<Hmm...makes me think bubbles generated from the tank drains is not the issue here>>
I have managed to cut out 97% of the bubbles that appear to be in the first container from reaching the pump intakes.  However that extra 3% is a good number of bubbles that I would love stop reaching my display, and I can see them just being pushed  along the baffles and getting drawn down into the pump intakes.
<<Interesting...I would think with a good baffle system; and considering the distance of travel/the relatively slow water flow, that the bubbles would be easily dispersed.  I wonder if there is any other equipment along the way that could be generating more bubbles?  Maybe the skimmer?>>
I'm thinking that I need to reduce the number of bubbles that escape the very first container, it is approximately 12”x14” and 12" deep and I can hardly see the bottom due to the number of bubbles.
<<Ahh, okay...wow...that is a LOT of bubbles!  Sounds like you have a major air entrainment problem>>
I have a plan to perhaps take out this container so that water is entering into the next container which is a good bit larger.
<<From what you describe I don’t think this is the best plan of attack>>
I'm thinking I would have room to build a manifold system similar to those built for aquarium returns but have the water drain into it where it can be slowly released from a number of smaller exits as opposed to just the two 1" pipes.
<<Not sure I follow this...but a series of “over-under” baffles in the first container should have been able to deal with many of the bubbles>>
Do you see any potential problems with doing this?
<<Not “problems”...just don’t see it resolving your issue if you have as many bubbles as indicated>
Do you suppose it would work?
<<Dunno>>
I can't figure out why it wouldn't but I don't want to build this thing if someone else can quickly tell me why it would fail.
<<Can’t do that without better “detail” of what you plan.  But try this...throttle back the flow from the pumps and see if the bubbles decrease significantly.  Measure your true flow to the tank (time the filling of a container of known size) and adjust to about 300 gph per each 1” drain (175 gph for ¾” drains).  Most drain calculators/schedules will tell you these drains can handle twice this flow, but it is my opinion/experience that reducing by half is much more practical/less problematic to deal with and the flow will still be quite ample for the sump.  Also, make sure your drains are all absolutely at the same height.  If one is a bit lower than the other the flow through this can be significantly higher; causing the excessive bubbles.  If flow is not the issue, then look in to aspirating the drain lines and/or adding an ell to the termination point of the line in the sump.  The former will help release entrained air in the drain lines while the latter helps to guide bubbles away so they don’t rise back in to the line blocking flow/creating more turbulence>>
Thanks, Kevin
<<Happy to assist.  Eric Russell>>

Micro-Bubbles/Drain Line Plumbing - 10/14/06
I have a 215G Oceanic Reef-Ready that came as is from the factory.  I thought I did my homework and then some when ordering this tank, but I have since learned that the drains are inadequate for this size tank.
<<A common enough opinion/fact that you'd think the manufacturer would eventually "get it">>
Redrilling this thing really is not an option at this point so I need to make best with the situation that I have.
<<Can be done, yes>>
I'm running 2 Mag-Drive 7's for my returns, I'm figuring that I'm pushing about 700-800gph combined with the 2 pumps after figuring in head pressure.
<<This should pretty much "max out" the 1" drains>>
I have two Vortec pumps to provide additional circulation within the aquarium.
<<Excellent>>
The two 1" drains are handling this with no real noise issues.
<<Good...often this is not the case>>
The problem I'm having is with micro-bubbles, I'm not sure if this would be related at all to the inadequate drains.
<<Could be/probably is...nowhere for the entrained air to go...>>
I'm doing a container with a container sump system using Rubbermaid Totes.  I figured that my problem was the result of not enough baffling, but I have since read the opinion of one of your crew members that micro-bubbles are not the result of the water returning from the drain, instead they are only formed in pressurized situations.
<<Hmm...>>
Is this fact, or just his opinion?
<<I have no wish to second-guess others of the Crew (especially without knowing the reasoning), but I suspect both (opinion based on some fact).  But that said, I don't agree that micro-bubbles would only be present in "pressurized situations."  As with the case of venturi-style skimmers, the bubbles can be the result of trapped air and water turbulence...in "my" opinion.  Maybe it comes down to the individual interpretations for "micro-bubbles," but I have witnessed some very fine bubbles emitting from drain lines over the years>>
I poured a glass of water in my tank and saw large bubbles near the surface and very fine bubbles deeper in the tank, similar to the micro-bubbles that I have.
<<Indeed...much the same as what is happening in your drain lines>>
If it is true then my problem must lie within my plumbing work or the pumps themselves.
<<Bingo!>>
I don't want to reconfigure my baffling setup if I'm not getting rid of the source.
<<Hmm...well...supposedly the "baffling" should handle any bubble issues (is why it is there), but excessive quantities of very small bubbles can be very difficult to "baffle out."  I agree with your stance to attach the source of the bubbles>>
I did the Vaseline test on all plumbing connections and that didn't seem to help.
<<Do be sure to clean the joints of any residual Vaseline to preclude possible deterioration of the plastic from the petroleum elements (Bob "cringes" at the use of this product).  It's likely the problem stems from the fact you have the drains pretty much at their maximum potential.  "Noise" isn't the only problem associated with overloaded drains.  I think your problem is entrained air due to the amount of water you're pushing through these 1" drains...aspirating the drains may provide relief.  This involves inserting small-diameter tubing at the highest point in the line to allow trapped air a route of escape.  The exact diameter and length of insertion requires a bit of experimentation>>
I have two 30G totes as my main sumps, linked together through bulkheads.  One was going to be a refugium.  I'm now thinking that perhaps I should now use the refugium tote to provide additional room for dealing with the micro-bubbles so I can have more containers and hence more baffling.
<<Mmm, I like the idea of the refugium.  I would look to aspirating the drain lines...you could also try using just one return pump to reduce flow in the drains (would still be plenty of flow through the sump/refugium in my opinion>>
I also seem to have what appears to be a bunch of fine particles in my saltwater, like dust in the air, only seen when turning the lights off and shining a light through the tank from one side and viewing from another.
<<Hmm, do you have a fine substrate?  Bioturbators?  I wouldn't be concerned>>
I'm sure after all the work I have been doing in an attempt to rid myself of the bubbles I have introduced a good bit of dust into the tank.  The tank was filled with purified water, so the source is not my source water.  But I'm not sure if this can be related in anyway to micro-bubble formation, or if everyone who did the same thing would see it in their tanks as well.   Can you tell me what would be the best way in using a sump system such as this to filter out these fine particles?
<<Some folks use filter socks on their returns.  I am not a fan of these as they trap detritus (obviously) and require constant maintenance/attention to keep them clean/become a source of decaying organics.  Personally, I wouldn't bother/worry about some particulates in the water>>
I have already drained this tank once, and it would take a lot to have to do so again.
&