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FAQs on Supplementing With Kalkwasser, Trouble/Fixing

Related Articles: Calcium, Understanding Calcium & Alkalinity, Kalkwasser, Calcium Reactors

Related FAQs: Kalkwasser 1Kalkwasser 2, Kalkwasser 3, Kalkwasser 4, & FAQs on Kalk: Rationale/Use, Calcium Measuring/Test Kits, Sources of Calcium, Calcium Supplements, Mixing/Storing Kalkwasser, Dosing Kalkwasser, Kalk Reactors, Kalk Automation, Alkalinity Interactions, About Kalk Use & Other Supplements, e.g. Magnesium, CaCl2 (Calcium Chloride)/ Pickling Lime Use, Calcium and Alkalinity

Please... Do NOT just pour "it in"... w/o testing, knowing your calcium and alkalinity (and Magnesium) demand, you will easily throw off your overall water chemistry. RMF

Re: skimmer maintenance, now DSB, Kalk Slurry concretes: Avoidance   12/27/10
Hey Bob,
Thanks for getting back to me.
I've decided to go back to a DSB in my DT. I had a 5" DSB that I removed because the top layer began to fuse together. I thought this was a bad sign and was experiencing problems at the time so I pulled it. I've been reading a lot of FAQs about sand beds and it seems that some people who use the slurry method to dose Kalk have experienced this same problem.
<Yes. Quite common>
While I was dosing using the slurry method, I would watch my PH meter to make sure I never got an increase of more than .2 . Do you think that going back to a Two part regimen for Calcium/alkalinity maintenance would avoid this problem?
<Should, yes>
It seems that the PH spike causes this fusing of the substrate.
<This is so>
Also, my corals grew much faster when I had the DSB compared to the BB tank I have now. This is one of the main reasons I am going back to a DSB. I did not have a refugium on this tank so the PH would drop at night and the sand bed would dissolve a little bit every night I guess.
<Mostly during this time... of lower pH>
I am planning on adding a refugium with RDP along with this new 6" DSB. I am concerned that the RDP will not allow the sand bed to dissolve because my PH will be kept elevated and extremely stable. Am I wrong about this?
<Only to an extent>
Will the corals not grow as fast due to this? Would it be better to run the refugium lights at the same as the DT?
<I would run the refugium, with the alternating light periods>
Would it be better to move the majority of the LR from my DT, that houses the DSB, to the refugium with the Chaeto?
<Not IMO, no>
I'm concerned about all the detritus produced by the animals in the LR will clog up the sand bed. I have also read that LR in your sump becomes a nutrient trap. Is this simply due to low flow just like a sand bed in a sump can become a trap?
<With care, consideration taken to not overfeed, regular alternate gravel-vacuuming during water changes, not problematical>
Sorry about the long email. Thanks. As always, it's very much appreciated.
<Certainly welcome. BobF>

Does Kalk dosing bleach coralline algae? Can 01/13/10
I recently started dosing Kalk wasser with the objective of raising pH, alkalinity and calcium levels as all have been low for several months. My coralline algae is now turning white.
In case you are going to post this, I will refrain from the entire equipment list, as I realize those posts can be very chewy. I'll just give the basics:
*1.5 year old system with approx 375 gallons of system water (280G MDT, 55G 7inch DSB (sugar fine) fuge and 90G sump that has approx 40G during run time).
*FOWLR with 1-2 inch medium substrate, approx 200lb live rock.
*Good turn over via 2 return pumps and power heads in MDT - turn over 15+ times an hour.
*I run carbon and D-D Rowa Phosban in TLF reactors
*Gigundo recirc skimmer which is a Warner Marine knock-off (18 inch diameter, 3 foot tall, 3 Sedra 9000 pumps).
*Fuge has Chaeto macro and a few rocks in addition to the 7 inch DSB.
*400W PC (half actinic and half 10K)
*No mechanical filtration used in the way of socks, pre-filters on pumps, etc.
*Only 10 fish totaling approx 30 inches. I haven't added any new fish in 6 months, because I wanted to get my green hair algae problem under control which has not yet happened - but that GHA issue is not the objective of this request.
parameters before Kalk dosing started approximately 2 weeks ago:
temp 79.0
Salinity 1.025
phosphate and nitrate give me 0 readings but I know false - locked up in the piles of GHA I have been battling for months now
pH 7.85
Mag 1300
Alk anywhere from 4.0 to 7.0 KH (depending on how long after last water change and how much buffer I added)
calc anywhere from 390 to 350 (goes with the Alk - I think I understand the marble analogy)
I started dosing Kalk because my pH was chronically low <Ok, but, generally, you don't use Kalk to increase pH (though it can help). Do you have a lid on this tank? It might be that you have high CO2 in your water... not enough aeration.>
and I have always used Alk buffers (Kent) to raise Alk / pH following my weekly 65-100 gallon RODI based water changes, but not only was that getting very expensive, it was not keeping my alkalinity in check and therefore pH constantly wavering and always ending up toward low acceptable end. For the first year or so the tank was established, I only use to do 35G weekly water changes (always RODI which is tested with TDS meter) but once the GHA kicked in, I stepped it up to 70G (2 Rubbermaid), and at one point used 3 (105 gallon). I think it was around the time I increased the water changes to 100G per week that my Alk (and pH) took a nose dive? I aerate the RODI fresh water for a couple days before adding salt mix (Oceanic) and then aerate salt water another few days before water change.
I do not buffer the water change water before using.
<You should. A buffer *maintains* pH.>
Every time I have tried to buffer the water change water (either before adding salt mix or after adding salt mix) the entire contents turn milk white, so I don't do that anymore.
<Ok, there's no real need to aerate the change water before adding the salt. If it were me, I'd add the salt and buffer to the RODI, then aerate for a few days. By then, the water should clear up and everything should be nice and buffered and aerated.>
BTW - the massive weekly water changes had no impact on GHA whatsoever (maybe I have a super strand), so I now do more like 40-50G water changes per week.
<Have you checked to make sure your RODI filter is working properly? Do you have a TDS meter?><<See above. RMF>>
So back to the objective of this dissertation: I wanted to find a cheaper solution to my low Alk / low pH problem, so I scoured WWM for dozens and dozens of hours to try and educate myself. I settled on dosing Kalk, because I thought I had a good handle on how / why / what it would do for me. I believe if I can ever get my pH to stabilize above 8.0, then the 7 inch DSB of aragonite sugar fine sand SHOULD help maintain decent Alk levels right?
<Unfortunately, imo, this is a bit of bad info that has managed to linger on WWM... sugar fine aragonite will not help maintain your Alk levels to any appreciable degree.>
That's why I am going down this path anyway. So now for approximately 2 weeks, I have been mixing up 2 teaspoons of the Kent Kalk mix in RODI water in a 1 gallon milk jug, shaken vigorously, and capped for at least 7 hours before slow dripping to high flow area of sump. I use 2 of these 1G mixes per day
<For 375g system, you might need more than this starting out.>
and only at night time when MDT lights off and only drip the super saturated portion. Since I have started my new parameters are:
pH 8.05 to 8.10
Alk 8.0 KH
<These parameters are probably ok.>
calcium 340-360 - going down marginally??!
Mag 1400 (I have dosed some Mag a couple times since starting the Kalk dosing with hopes calcium would increase)
I can live with these numbers although I assumed they would be higher and I don't understand why calcium levels are actually dropping a little?
<There could be lots of reasons for this... it might be settling out or being taken up by invertebrates...>
I have 2 different calcium test kits and they are both giving identical readings. I even brought water to LFS and they have confirmed.
But regardless of the new parameters, now all of my coralline is bleaching out!
<Hmm... maybe it's being out bid for nutrients by the green hair algae?>
That's the coralline on the live rocks, on the back and sides of MDT, in fuge and skimmer, etc. I have also noticed clumping of the sand in the DSB of fuge. I should note that the DSB in fuge has only been in place for 4 or 5 weeks. Previously, the fuge only had a 2-3 inch medium grade aragonite substrate.
Is this bleaching normal? Should I stop dosing the Kalk?
<I don't think you should stop dosing Kalk. It's possible the coralline didn't appreciate the "sudden" change in parameters (but if that's the case, it should come back after the system has been stable for awhile).
Regardless, something seems a bit "wrong" about your system in general.
Where are all these nutrients coming from in a 375g tank with only 10 fish?
Seems odd. What are you feeding the tank?>
Thank you very much for your invaluable resources / service you guys offer here by the way!
<Our pleasure.>
Not to mention, thank you for spending half your night reading this lengthy post, and I really hope you can further educate me as to what might be going on here.
<I'd test your RODI water with a TDS meter... and try to figure out why you have this algae problem. What are you feeding the tank? What other supplements are you using? Are you sure you have enough aeration in the system? Do you have the "right" invertebrates for clean up, etc.?
Because, despite your respectable efforts, your system is "off balance."
Something isn't quite right somewhere...>
Sara M.>

Re: does Kalk dosing bleach coralline algae?   1/14/10
Wow - that was fast. Thanks very much for the input. To answer some of your questions, here goes:
Yes I do use a TDS meter and change my RODI filters out as soon as I get to 10 ppm. The meter typically reads 0 ppm.
I do not have a lid on MDT, nor on sump, nor on fuge. I may indeed have high CO2 as this is an in-wall display (and 2 year old home) with fish room (that has no exterior windows),
<Yikes... this might be part of your problem if the air around the tank is essentially "sealed off." I would definitely think of some way to remedy this (put a vent in the wall if need be).>
but I tried keeping window open and running series of fans from it to fish room for most of the summer and although my pH did increase a bit, it was not appreciable.
<What are you calling "not appreciable?" Mind you, every 1 unit change in pH is actually a 10x change in concentration of H+. So if your pH went up from 8.0 to 8.1, that might not seem like much, but it is.>
I have a TON of aeration going on. The return pumps alone turn over entire system volume 8x an hour, and I let my 1.5 inch drains (2 of them) splash a decent distant above sump water line. I also have fuge draining into sump, and external skimmer draining into sump, each allowed to splash (drain pipe above sump water level). Not to mention a bunch of powerheads in MDT and fuge with some pointed to water surface to really agitate.
<I'd keep the door to the fish room open, or cut out a vent in the wall...>
I can try buffering water change water again, to see if this time it yields any differences from prior attempts.
<It's worth a try, imo.>
I don't know why I have such a terrible nutrients problem to be honest, and could write an even longer diatribe about my battle with GHA and all of the efforts (and thousands of dollars)
I have invested into trying to address that. I can say that I put a large clean up crew (50+ hermits, 50+ snails, etc) in MDT a few months after start up, and within a month of adding trigger and wrasse they were basically all gone. So I have always speculated that their mass die off (whether eaten by the fish, or refusal to expose themselves for fear of meeting same fate they saw their buddies meet (picture wrasse banging hermit against live rock for a snack)) introduced a huge nutrient spike?
<That's possible.>
I also had a fish die and fall into live rock structure that by the time I tore the rock mass apart to get his decaying body out (a week or so later)
it was gone! Apparently my clean up crew was working really well??
Lastly, I also had an under powered skimmer for a while. So all I can come up with is that I had this huge nutrient build up early on, and am still paying the price because I have been so diligent for the past 9 months I am 100% positive I should be pulling them out faster than I am putting them in. I do not dose anything beyond alkalinity buffers previously and now Kalk. Very infrequently, I dose magnesium (as in 3 or 4 times a year). I feed only once a day, and am very judicious about amounts (food never hits the substrate, because the amounts I add are snagged immediately by the team). I even abandoned Selcon soaks thinking that may be cause. I use high quality seafood (raw), Nori, etc. I never dump thawing water in tank.
I have read every article on WWM and other sites about controlling nutrients, and I practice every suggested method religiously. So again, I have NO idea why I have this GHA that just won't go away. I continue to assume I have the super strand that no one knows about :>)
<Hmm, not likely though. If you're up to trying (yet again), I can tell you what I'd do. This is a huge system, I know, but I'd:
1) start pulling out the GHA itself--granted, this won't be easy, but I'd start scrapping it off and sucking it up as much as possible
2) dump out 3 to 4in of this 7in DSB you've got in your fuge (imo, the added utility of a sand bed declines exponentially after 4in)
3) Use the extra space in the fuge to grow more macro algae in the fuge/sump --try a different type or two of macroalgae besides the Chaeto (maybe even use a better light on the fuge if you think you need it)
4) get some tough, competitive soft corals like xenia and Zoanthids (specifically ones from friends or LFS that you know are resilient, fast growing and bullies in the aquarium). >
But are you saying my high nutrients can somehow play havoc with coralline - but only with the introduction of Kalk?
<No, I'm saying that, maybe your GHA is out-competing your coralline.
Coralline algae needs nutrients too. If the GHA is sucking them all up, then there won't be much for the coralline. More likely though, I think it was just the sudden change in Alk and pH that upset the coralline algae. I think it will come back after your tank parameters stabilize.>
Coralline flourished until I started adding the Kalk.....??
<Yeah, exactly.>
Again, thank you very much for your time and knowledge sharing!
<I wish you luck... you know, this is often a game of hit and miss. You just have to keep trying different things until you figure out what works for your system. It's frustrating, I know. :-)>
Sara M.>
P.S. I'd also get rid of the crushed coral (or "medium substrate") in your display... this stuff is of little to no use to anything (and, imo, often just traps fish poo). Put in a layer of sand or just go BB. Again... just my opinion here. - Sara M.

Kalkwasser <<Mis>>Application -- 03/19/09
Ok. I guess I'm an idiot.
I've been in this hobby for oh about 3 years now learning way more stuff than I ever thought would be needed to "have an aquarium".
Maybe 8 months into the thing I graduated to using Kalkwasser.
<<Pros and cons to its use'¦ But I do use it myself>>
I think from that point till the present I have been using it incorrectly but not to the point of devastation obviously because all systems are going ok I guess.
This is going to sound really stupid especially from someone who has dedicated a lot of time to reading books and internet research like this site but I have been under the impression (my own) that Kalkwasser because of the way it settles in a reservoir after mixing with your water, needs obvious aeration to keep Kalkwasser ingredients suspended while it drips into my aquarium.
<<Um, nope'¦ Doing so can/will actually render the solution moot as the introduced Carbon Dioxide from the aeration will react with the dissolved Ca++ to form much less soluble CaC03 (Calcium Carbonate)>>
What possible benefit could come from the stuff if it just sits at the bottom of the reservoir giving me clear water for the output?
<<Mmm, your research should have enlightened you to the fact that after mixing, the 'clear water' is a concentrated solution of Ca++ and OH- ions>>
So here all this time I have a fancy rig set up which is my 29 gallon Rubbermaid can in the laundry room (lid on- don't go all laundry chemicals on me right now I can't take it), with proper dosage of Kalk spooned in. Then one large Rio pump stirring that whole mess up so it doesn't settle to the bottom, and one small pump at the bottom which is attached to my 1/4" airline tubing that runs up and over the can, through the laundry wall, into other room where the "reef" is and into the sump. I have a valve on the end of the tube to control the drips to maintain the proper water level in my sump.
<<Not a bad setup'¦other than the Rio only needs to be used 'periodically' to stir the Kalkwasser>>
It's been a real bugger clogging with that milky Kalk dripping through there.
<<No doubt>>
So periodically I open the valve more to push the obstruction through and reset. It doesn't take much and tank inhabitants don't "appear" to mind.
<<The 'obstruction' is likely mostly insoluble Calcium Carbonate from exposure to atmospheric Carbon Dioxide'¦along with whatever impurities are carried along in the solid particles>>
All on my own I decided that I needed to try something else because that was becoming a pain. So I decided to do like some other people and go with the two part ESV stuff for calcium and such.
Just got it today and haven't even opened them yet, but I do promise to be careful.
<<Just follow the manufacturer's instructions'¦along with water testing for need of the supplement>>
I figure, without the Kalk issue, I can have more consistent top-off water without the clogging and get my calcium elsewhere.
<<Several approaches to dosing this bio-mineral, yes>>
Now that I see from further research, it appears I could go back to the Kalk and mix initially but this time just let it settle and that's ok I guess.
<<Many hobbyists do use this approach with success>>
So correct me if I'm wrong please.
<<Not wrong'¦ Do look on the NET for the excellent articles on Kalkwasser/Kalkwasser dosing by Randy Holmes-Farley. Here's a link for starters: http://reefkeeping.com/issues/2005-01/rhf/index.php>>
Sorry for the run on sentences and any other poor grammar or misspelled words or other errors.
<<Spell-check is a wonderful tool>>
<<Cheers, EricR>>

Re: Kalkwasser <<Mis>>Application -- 03/20/09
Thank you for the link on the correct procedures for administering Kalkwasser.
<<Quite welcome>>
I still have a couple quick questions I'm sure you will know the answer to.
You say I need to "periodically" stir/aerate the Kalk with my Rio pump. Define periodically.
<<Not 'aerate''¦but 'stir' the Kalkwasser to saturate the stock solution. When using a 'reactor' where new fresh water comes in to the vessel to replace that dosed to the tank then you would want the pump to 'periodically' stir the mix (run for a couple minutes, two or three times over a 24hr period) to ensure dissolution of the powder/saturation of the water. If the Kalkwasser is not being utilized in a reactor, but is simply dripped or pumped from a container, then you only need to run the pump to stir the mix when new water or Kalkwasser powder is added to the storage vessel>>
If I'm using a 29 gallon can and it's nearly full of Kalkwasser solution, and my evaporation rate is about one drop/second refilling back into my sump (155 total gallon system with halides), how much stirring do I need over the course of about a week (depletion)?
<<If no new water is added during this period then additional mixing is not necessary. Once you do the initial mixing and the solids settle out, the stock solution is saturated at that point and as long as new fresh water is not introduced to the container, any additional mixing/stirring of the solid material is moot. I do also want to mention that once the clear solution has been used up and you are ready to add more water to the mixing container that it is not necessarily so that you also need to add more Kalkwasser at this time. It depends on how much Kalk powder you begin with, but more often than not there is more than can be dissolved/utilized in one go. Try just adding more fresh water, mix it well with the Kalkwasser solids in the container, allow the solids to settle out and test the pH of the water. If the pH is 11-12 then you should be able to use the new stock solution without adding more powder>>
Also, once this is empty, do I discard the remaining solid(s) at the bottom of the can or leave it in there? I've never removed solid Kalk before because it had previously all been mixed up and administered.
<<Ah'¦I should start reading ahead'¦ It's up to you, but I reuse this material. You will accumulate insoluble material, so do figure on dumping/cleaning all a few times a year>>
One other thing, is there a pH/temp tester out there that is head and shoulders above the rest?
<<I find the Pinpoint electronic meters from American Marine to perform well>>
Or all they all problematic?
<<They all require care/maintenance/periodic calibration or replacement of the electrodes>>
I was looking into a Hanna 5 pH/temp tester but want your input first.
<<A lot of folks use these 'portable' meters but I find the electrodes of the larger 'monitor' type meters like those offered by American Marine to be more durable and easier to keep calibrated'¦and easily replaced as needed>>
Thanks again, you people are a tremendous asset to the hobby.
<<Many thanks for the kind words'¦is a pleasure to assist. Eric Russell>>

Kalkwasser vs. Bubble Algae   8/23/08 Hi Bob, <Kiwi> I have a question for you. I was using Kalkwasser to kill off some aiptasia <Mmm, wouldn't do this... Do look into Red Sea's newest product for... really spiffy> and got some Kalk on the bubble algae cluster adjacent to the anemone. <Oops> Two days later the cluster of bubble algae was dead and gone. Have you tried this? <Nope> Is it safe? <Not likely... the killing, dissolving of disparate life "in" system is often problematical... the release of all sorts of chemicals, cells...> I haven't seen any ill affects in the tank. I do however; wonder if the spores of the bubble algae were released since it was entirely covered in Kalk? <Don't know... but would not be surprised> Any ideas as to how or what happened? Sincerely, Kiwi <Caustic, basic "burn" reaction... toxified the algae to the extent that it "gave up". Likely, as you state, this material dissolved as a reflex defensive mechanism... is now spreading throughout the system. Cheers! Bob Fenner> Qiwen "Kiwi" Feng Aquatic Express Inc. 451 Grandview Avenue, Ridgewood, NY 11385

Kalk Slurry FAQ corrections  7/3/08 Greetings! While researching Kalk dosing I came across a minor error on this page: http://www.wetwebmedia.com/kalkh20faq2.htm, 10th entry from the top. Here is the abbreviated text: "Kalk Slurry - 2/17/03 what is the proper way to add Kalk slurry and how much water should be used? <.... Be sure to use a digital pH meter to prevent spikes of more than .02> ... <...with kind regards, Anthony>" The decimal should be moved from .02 to .2, <Agreed... will append> as Anthony actually states in the previous entry on that same page! I have one additional concern -- although various opinions exist concerning the usage of Kalkwasser, I believe the term "Kalk Slurry" is assumed to have a universal definition by most readers in the hobby (or at least it should IMO). <A good... but incorrect assumption> The conflict of information I came across concerns whether or not to dump the solids into the tank along with the cloudy water (basically everything in the cup) versus decanting the mixture, as it pertains specifically to the Kalk Slurry method. In today's FAQ the reader is advised to decant the solution: "Kalkwasser Slurry method - 7/2/08 I've been reading about the Kalk slurry method on your site as well as other sites. I just wanted some clarification on this method. I know your supposed start with a 1/8 or 1/16 of a teaspoon of powdered Kalk added to cool or cold RO water, mix it and add the slurry slowly to the main tank. What I'm not clear on is... I've only read one article that mentions...you should only add the cloudy water layer...not the precipitated Calcium Hydroxide solids on the bottom. <Yes... best to decant, otherwise avoid introducing the solids>" <Yes... my stmt.> In an archived FAQ located here: http://www.wetwebmedia.com/kalkh20faq2.htm, the reader is advised that the slurry method involves dumping the powder in as well; Calcium hydroxide grades - 2/15/03 ... "<if you dose by a supersaturated solution and discard the minor precipitate, then you can get the cheaper product. Kalkwasser is self-purifying because of its caustic nature. At the high pH of the solution, most metals and contaminants precipitate out. Now... if you intend to dose the powder directly (like my Kalk slurry method mentioned on WWM and in my book), then you will want to buy the better grade> <thanks kindly, Anthony>" Given that the definition of a slurry describes solids suspended in a liquid without completely dissolving, I would lean toward the latter answer in determining a universal definition for Kalk Slurry. I hope this is of some use to the site, my tank inhabitants thank you all for your dedicated efforts and hard-earned knowledge. Regards, Brandon <Thank you for your efforts at clarification. BobF>

Ugh, These Blasted Test Kits!...And Maybe A Little Kalkwasser Seesaw Effect? -- 03/18/08 Yep, admittedly I fell prey to bad test kits, first with alkalinity and then with magnesium. <<Very common, in my opinion>> Here is my issue, 1000 gallon system, my reactor used to be able to maintain Alk and calc at appropriate levels, the test kit I was using (Red Sea as I couldn't get Salifert at the time) <<Do try Seachem's line of test kits'¦good quality for value>> for magnesium was reading 1200 ppm. Little did I know it was below that by 200ppm per my Elos kit, <<I'm not familiar with this brand/manufacturer'¦though I do seem to recall favorable comments from Bob re>> and I was using Kalk which was eroding it further. <<Mmm, yes'¦I'm not absolutely certain of the science behind it, but I believe it is something to do with the addition of Kalkwasser increasing the precipitation nuclei of the water column, thus promoting the disproportionate loss of Magnesium>> Needless to say I fell into this desperate addition of varying buffers to maintain Alk and calcium until magnesium finally hit 1300+ (I'd like to stabilize it at 1400, I'm running Zeo Mag in my reactor and it's putting out 1350). <<I think it likely the reactors and the Kalkwasser additions are battling each other'¦probably best to discontinue the latter>> So, long story short, tested my levels last night, Mag 1300, Alk 8, CA 400. My reactor ran all day, is well tuned in with a pH of 6.5 and Alk output off the scale. I dosed Kalk for a while today to raise pH as it was floating around 8.1 and I wanted to get it higher (dripping maybe 20 drips per minute, in a 1000 gal system I thought it was just about right). Tested Alk tonight and it was 7, CA 360 and Mag 1200! <<Refer to my previous statement re the Kalkwasser use>> I do have a little detritus but not a big buildup. I don't understand why I can't nail down solid levels. I increased the CA reactor output and it's a steady stream, but I am really wondering at this point if I am not best off adding another CA reactor. <<This would be preferable to the Kalkwasser additions>> I do have heavy SPS but I can't believe they are sucking that much calcium. <<If exhibiting heavy or even just 'good' growth their demand can be considerable>> I am beginning to wonder if I am not in some type of runaway supplement nightmare <<'¦yes>> (I add all according to directions), but the sheer fact that Mag fell by 100 in a day (per my Elos test), indicates to me stop dripping Kalk, use Seachem's buffer for pH if need be, and dose mg according to directions until it stabilizes. <<Sounds like a plan>> I don't have any nutrient sinks that I know of (only DSB is a DSB 30 gal trash but it has no detritus in it). Any help is greatly appreciated! <<Stopping the Kalkwasser dosing and stepping-up the Calcium reactor(s) should make a dif'¦oh!..as well as a large water change to help bring all back in 'balance.' Regards, EricR>>

Re: Possible Kalkwasser issue... with the link!   5/20/07 Bob, <Diego> Thank you again for the quick and useful reply. I'm still a little bit puzzled by what's happening and would like to share a couple of thoughts and questions to make sure I understand the problem. Here's what I'm struggling with. I. I understand that the danger parameters are not as hard walls as I may think, but if a snowstorm is happening wouldn't it cause fluctuations in parameters such as Ca and Alk. I measure them daily and they seem to remain pretty constant. <I see> II. I use a very low concentration of Kalkwasser since I don't have a huge consumption of calcium. I would expect this to reduce the risk of these events. <Yes> III. After further observation I realized that not all particles are white and many seem light brown. In addition they seem to be coming from the back of the tank following the water movement. <Okay> In addition to a snowstorm I was thinking it could be and accumulation of detritus in some area of the tank (hidden behind LR) that is being circled around by the water movement. My third hypothesis is that I'm incorrectly fishing in the Kalkwasser container, therefore exporting some of the precipitates that form while mixing. <Could easily be> I forgot to add that everything in the tank seems to be doing wonderfully. This is making me look at other hypothesis since I would think that Ca/Alk crashes would at least cause some stress. <Usually yes> I know I've been taking up a lot of your time but if possible wanted to ask one last question. When preparing RO/DI water to be used to mix saltwater, the best procedure would be to just mix it for 24hr with a powerhead or you would also buffer it to pH 8.4 before adding the salt? <I would buffer after adding the salt... In fact, any changes I would measure for and amend AFTER the salt is completely dissolved, the water circulated (otherwise aerated)> A huge thanks, Diego <Welcome my friend. Bob Fenner>

Re: Possible Kalkwasser issue... with the link! plus weird creatures in the sump. Bob, I hope your enjoying the Memorial day weekend. <Yes... thank you> Thanks again for the very useful answers. I took some observation time to understand the origin of the particles that I'm seeing. After some tests interrupting the Kalkwasser, I'm pretty sure that it's detritus floating around along with some microbubbles. I'm wondering now if there is a safe level of detritus that can be suspended in the water or if it's always better to minimize that? <Mmm, no, not always. The vast majority of biomass in aquatic environments relies on this material (active and not) through filter-feeding mechanisms for nutrition> Is this true also for air bubbles? <These may be trouble, and cured through various interventions... depending on their cause http://wetwebmedia.com/bubtroubfaqs.htm> I realized that the bubbles aren't coming form the skimmer operation so I'm thinking that it might be difficult to get rid of them. My main problem here is that I started noticing this when I installed my new MH lights and I can't see these particles when only the actinics are working, therefore I'm also thinking that it may have always been like that. <Maybe> On a second note I would really appreciate your help on identifying some weird creatures that I found in my sump (see attached pic: sump). While cleaning the skimmer I saw what seemed to be small bags of eggs with rabbit like ears, attached to the sump. I hope that the picture is clear enough (the yellow color is caused by the wooden structure, the water is colorless). The sump is full of these bags all around the bottom. I'm wondering if this could be in someway connected to the particles I'm seeing in the main tank? <Mmm, not likely... these look like small Sea Cucumbers to me http://wetwebmedia.com/cukeidfaqs.htm> During my studies in the US I was working on a project related to growing algae for CO2 sequestration and I just realized that some parts of that project could be extended to reef keeping. <Ah yes> In particular I was wondering if you know of any tank lighted with fiber optics and a solar collector? <Not yet> It would be possible to concentrate the solar light using a collector on the roof and use the fiber optics to transport the light to the tank. It would need some calculation but I'm thinking that in areas with enough sunlight it would save a lot of electricity? <Yes> I'm sorry but when I start talking about my passions I really get carried on. If I can add one more thing, I wanted to send you a couple of underwater pictures that I took in Hawaii. <I see your Auriga BF> I don't know if you use reader's picture for the daily pics and don't want to look too presumptuous in sending them. I'm always surprised in how the behavior changes from the ocean to the tank. Non reef safe fish live along with corals and very territorial fish in tanks, live in schools. I guess scale here makes the big difference. <We are in agreement my friend> Thank you for your patience, <And you for your participation. Bob Fenner>


Re: Kalkwasser, pH, dKH...And the Need for Understanding -- 04/15/07 Hi Eric <<Hello Roger>> Thanks for the in depth reply. <<Hope it helps>> I will indeed read all the suggested material. <<Please do my friend...and beyond what was suggested.  Knowledge is indeed powerful here>> My Ca reading is 400 following the Kalk incident! <<Ahh, ok...this is fine>> And yes it is the dKH reading which is 13. <<A "bit" high as stated, but no reason to panic...just let it fall naturally>> Could it be I was doing OK before I followed the erroneous advice on using Kalk? <<I think so, yes>> Apart from the Nitrates being constantly at the 12ppm mark, everything else seems fine, oh except the pH which is perhaps something I'm worrying about wrongly and what I was hoping the Kalk would cure. <<Indeed...  Though at the "low" end the pH is not "bad" but it wouldn't hurt to boost it a bit for some measure of a safety cushion.  I suggest you try the Seachem product 'Reef Booster' for this...buffering your saltwater mix just prior to doing your water changes should work nicely>> My reasoning on the c02 issue was I'd read that that might be a cause of low pH. <<I see...  This shouldn't be an issue with an "open" top tank, use of a skimmer, and good water flow within the tank itself...unless your home is sealed tightly and the CO2 levels within are high (easily tested by aerating some tank water outside the house for a while and measuring the pH)>> With nitrates the level has never changed since I started testing it 6 months ago. <<I would try a new/another brand test kit to validate this>> My LFS state that theirs is 25 and think my level is good!!!! <<It's not "awful," but is higher than I like to see on a consistent basis.  Perhaps you could add some Chemi-Pure or Poly-Filter to your filter path to see it this helps bring it down>> Any advice would be gratefully received.  I was using a canister filter with bio balls and noodles (heard theses were nitrate factories) so have managed to remove them over time so that the filter now is used for water movement and small particle removal only, so now the LR and sand are keeping the bio filtration spot on but no change in nitrate levels! <<Do make sure you clean the particulate filter "at least" weekly as the trapped detritus is a prime source of nitrates.  And this canister filter is a great place to place the chemical filtrates mentioned>> Thanks once again, Roger <<Quite welcome.  EricR>>

Nuclear Meltdown Bob, I am still in a state of morning. I left Tuesday for a convention in Atlantic City, NJ. When I left that morning my 75g reef tank was doing well. I left a neighbor (familiar w/ aquariums) to watch over my tank. When I got home Thursday night, I went to check the tank and noticed it was cloudy. Then I looked at all of the carnage. Everything in my tank had been killed off. The fish, inverts, hermits and even the bristleworms (didn't know I had that many!) I was able to save approx. 12 left-handed hermits and 1 green stripe goby. These were quickly placed in my quarantine tank and are doing fine. I could tell from the smell that my ammonia levels hit the top of the charts. I attribute the die-off to 2 possible solutions. The first the use of Kalkwasser. I think it became too caustic.  <This stuff is way too toxic for its intended use period... a very poor idea/choice in folks trying to sell "something" to the public IMO...> The second I am unsure about. My neighbor noticed that my protein skimmer was not working. He assumed that I had unplugged the unit. Would a failure like this create this sort of problem? <Yikes, oh yes... a chain of bad reactions> Also, is the live rock worth saving? I'm talking about a nuclear explosion. Am I back to square one? <Yes, worth saving... if nothing else, not too hard to re-culture with some new LR on/over the old. And yes to being near to square one> Thanks for your insights as usual. Bob Wrigley <Very sorry to hear of your losses, troubles. Patience and retrospection my friend. Such adversity can be instructional. Bob Fenner>

Substrate Compaction Hello again, Bob. Thank you for such a speedy response on my questions. I tapped into the water line before my softener to the R/O. Man, what a difference! My dkH went from .6 to 11.8.My calcium readings were like 170ppm(with the help of Turbo Calcium) to 280ppm with nothing but R/O water salt (partially softened water still mixed in, so my readings should get a little higher on my next batch). Hopefully, this will boost my coralline algae growth.. <Yes... good moves... you should see a difference with days to a few weeks> I also switched to Instant Ocean not mixed any yet). Another note; I've moved my rock to my 65 gallon tank I've just set back up. It is longer and shallower than the 58 gal. tank (better, right?). <In general yes> Besides, the 58 gal. was borrowed from my brother, which I had planned on purchasing from him, but would be better off using the money elsewhere. I've caught you up, so here's another problem: I've used Kalkwasser off and on in the past. I've also had a problem with substrate compaction. I don't always vacuum the gravel (Seaflor) like I should, but when I do, there are big chunks that are hard to break up. I've heard Kalkwasser causes this. Is there something I'm doing wrong or is this unavoidable? <These are likely related events... and yes to prevention... simple dragging of a wooden or plastic dowel/rod through the substrate during weekly maintenance will prevent a good deal of this compaction/aggregation> Would a larger substrate size help?  <Perhaps... or adding some to the existing> I also thought about not using a substrate, but I would lose my buffering. What would be my best option? Thanks in advance, Steve. <The best option? Not using the calcium hydroxide at all... but availing yourself of a carbon dioxide type calcium reactor... If you use the Kalk, only drip it in slowly... only at night... only in a vicinity of rapid water mixing... and only as much as needed... Many intermediate approaches to consider... Bob Fenner>

Live Sand Mr. Fenner, <Anthony Calfo in your service> I begin by saying thanks for the amazing service that you and the WWM provide. A wonderful and invaluable resource that borders on information overload!  <yes... we have been told that we are really full of it many times <G>> I have been able to research numerous topics with your FAQ's and your added Google search engine! Thank you. <excellent to hear> My question is about live sand. I am seeing "clumps" of sand -- I tried that in the search feature -- and have noticed that the grains seem to be sticking together. <yes, I understand and can explain it> Tank info: 58 Gallon + Wet Dry Ceramic Media)/skimmer + HOT Magnum Ammonia 0 Nitrite 0 Nitrate >10ppm pH 8.1 dKH 10 Calcium 400 I add the Kent CB as the tests warrant and had been using Aragamilk. <bingo... misapplication as part of the problem> My sand "crew" includes: <this has nothing to do with detritivore activity> Sand sifting star, Over-achieving Dragon Goby, <yes... Amblygobius phalaena: this goby is one of the very best and most hardy!!! for sand sifting. I love them> 10 Blue-legged hermits, and a Blue Damsel that has taken to re-arranging the sand in three of the four corners of the tank! What do these clumps indicate about my water chemistry?  <it is exactly precipitated (literally) by wildly fluctuating chemistry. Perhaps unnoticed by you if you test your pH at the same time every day. Some folks get it by pouring in Kalkwasser solutions too much or too fast which causes a temporary spike in pH locally. It may occur from the misapplication of other Ca or Alk products (like your Aragamilk product.. of which I am dubious about its benefits in the big picture) when used too much or too quickly (smaller more frequent dosing is better than large weekly doses. And finally it can happen in tanks (receiving such products or not) that have wild "natural" swings in pH between night and day. I see that you report a pH of 8.1. If this is accurate and a reading taken by day as I suspect (when pH in aquaria is highest by far)... then you have a borderline serious problem with pH. You may actually be dipping down to 7.8 or lower at night (tank respiration). And this is all assuming that your test kit read accurately! What if the kit read high? And your day night readings are actually 7.9/7.6...yikes! No wonder then aragonite in your bed is fusing.> Or is this supposed to happen?  <nope... an indication of a minor flaw in the system that could turn into something bigger. Still not much to worry about> Everything looks fabulous but I am noticing more of these little sand "balls" every day.  <yes... do examine your dosing system and day night pH swings (take a test reading after a long dark night before the lights come on and not after a fresh dose of ca/ALK)> I really did try to find this mentioned in the FAQ section and under LS but I may have been looking for the wrong thing. <appreciate you taking the time to look... hopefully you found other interesting things> Thanks for all your hard work and for sharing your expertise. Have a wonderful day. Lee <best regards, Anthony>

Kalkwasser still.... Hello again Anthony (It's only me from over the sea....) <Cheers, dear!> I don't know if you remember, probably not now but approx. 3 weeks ago I was asking about dosing my reef tank with Kalkwasser. I was worried about what I thought was high pH (8.5). Do I take it that 8.5 is actually not high?  <correct. It is indeed on the higher end... but a reef tank that was say 8.5 at peak day and dropped to 8.3 at night sounds nearly perfect to me> I say this because you said that a pH of 8.6 would precipitate my high phosphates, support Alk and add free calcium. I thought pH should be around 8.3? <8.3 is a convenient average and one that is promoted (driven) by industry production of overpriced sea buffers that are mostly baking soda which can only bring a system to 8.3 and no higher easily <wink>. NSW averages on actual reefs (not the whole ocean average which is lower) is around 8.45> I still have not started dosing as I am still worried about the affects . This is because I now test for calcium as well as Alkalinity. My tank is 100 gals (Imperial not US gals). The parameters I test for are: Temp normally 78 has crept up to 82 in last couple of days because of abnormally hot weather (for England that is!) <a four degree jump is a rather stressful... do keep a close eye> SG = 1.024 pH = 8.5 (8.3 at 2.00a.m. yawn!....) liquid drop and tablet tests agree here Ammonia = 0 ,Nitrite = 0, Nitrate between 10 and 20ppm Dry-Tabs Master test kit. Alkalinity = 250ppm (is this high?) Aquarium System Fastest Calcium = 500ppm + used all measured dose without sample water turning blue.. previous reading 3days ago 410ppm 10% water change done since then. Salifert CaPro:-Test <holy cow! The calcium reading is very hard to believe. If you aren't adding any other calcium supplements then you have EXTREMELY hard tap water or it is a clear inaccuracy of the test equipment. You are dangerously close if true to having carbonates precipitate out (a snowstorm). Please do not add ANY Kalkwasser until this is clarified.> phosphates = 5.0 (very high even straight from tap, main reason for wanting Kalkwasser, <WOW, yes... 5.0ppm is staggering. Terrible nuisance algae in the tank too?> hair algae plague))  <ahhh, yes> Dry tablets My question is this: Can you have too high a reading for calcium/alkalinity and if so what should be done?  <yes... both are not meant to be held at the high end of the ideal simultaneously. 8-12 dKH for ALK and 350-425ppm calcium is just fine> will dosing with Kalkwasser make the calcium /alkalinity readings even worse? <yes, but in different ways. If you push the Ca higher, you may drive the ALK lower through the crystalline precipitation of carbonates. A bad scene. You may need a RO or DI unit to temper your hard tap water. Starting with purified water, you can reconstitute the mix to a more reasonable Ca and ALK levels> I use Instant Ocean sea salt but am changing to Reef crystals when that runs out.  <please don't as long as you use tap water (if the high CA is true). You already have too much calcium> I tested freshly mixed Instant Ocean and found it had mixed a pH of 8.6 (thought it mixed 8.3 ?)  <usually yes, but you seem to have higher than normal hard water> I again used both dry tablet and liquid drop methods and they gave the same reading. I normally dose the tank, sparingly (less than recommended doses) with Iodine, Strontium and calcium once a week (no calcium for the last 3 weeks) since I realized how high it was but you see it has still gone up since then with no additive just a water change <ahhh.. no supplements, but the water change= definitely hard water evidenced by the jump in Ca. Do consider a DI unit to purify your water. A Kati Ani two column deionizer will be a fine investment> Taking all this into account , would you still dose with Kalkwasser ?<nope> I will just add that I have no room/capability of adding a sump/refugium under the tank much as I would like too, I am saving up for a tank that has all this incorporated in it but this will not be happening just yet! All inhabitants seem happy enough (touch wood!). Many thanks for all your past /future help , I am slowly learning with your help. I have not found any site anywhere with such an abundance of information and people willing to help like you do . Also I have learnt a new word from you , so Kudos to you! <excellent!:)> Bye for now - Jenny <until you make the investment in a water purifier, simply do water changes with Instant Ocean, add no calcium or buffer either so long as they are over 350ppm and 8 dKH respectively. Best regards, Anthony>

Re: Kalkwasser still.... Hi again Anthony What a lightning response!! <we aim to please! Actually... we are just looking for some good fish and chips when we finally do visit the UK :)> You have confirmed what I was thinking about not adding Kalkwasser yet/if ever. We do have very hard water here. <indeed... it all points to that. A blessing for keeping marines and African cichlids, but a nightmare for Amazon and pond fishes> I am now a bit (no, a lot) worried about this snowstorm thing you say I'm close to. Would it have happened when I did the water change if it was going to? Could it still happen and if so what can I do to either stop it or correct it if it happens.  <the event is unmistakable... it looks like snowflakes suddenly and massively appearing in your tank: like a snowstorm. I can say that you have nothing to worry about if you keep doing regular water changes (providing fresh minerals for the corals) and always replace evaporation with distilled water (else you will concentrate the solids in the display by using tap water for evap top off)> will I lose my tank inhabitants?  <it can be fatal yes and must be allowed to run its course... doing a water change during the snowstorm only feeds the reaction with more carbonates. You will be OK if you don't let your Calcium climb above 500 ppm approx> I was going to do another water change soon but I dare not now!  <please do! The water changes are necessary and critical. Your tank draws calcium daily... the water changes help to replace it. You simply must add the distilled or RO water for evaporation make up and you will be fine> Please clarify my next move apart from getting a RO or DI unit (I know what a reverse osmosis unit does but what is/does a DI unit please?) which would you most recommend me to get . <DI is a deionizer and quite similar to an RO unit. Much better in my opinion because it produces no waste water. It can also be fully recharged with household chemicals> Thanks again for such a fast response - I am very grateful. Jenny <My pleasure. Anthony Calfo>

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