Temperature Fluctuation
Hi again. <Hi, MacL here with you tonight> I am a little worried about my water temperature, I really don't know where it should be right know it is at 26 degrees Celsius <26 degrees Celsius, equals 78.8 Fahrenheit which is generally considered the perfect temperature to keep saltwater tanks.> and when I turn on the a/c it changes. <The big question is how much does it change. Large fluctuations 3 to 4 degrees can mean real problems for the tank.> I would like to know what are the degrees of changes I should have so it is ok for the fish. I don't have a chiller, I live in Panama in central America so here it is hot all year round, <Lucky person> the tank is in my room and the a/c is almost off all day and on in the night and when I leave sometimes it stays off for the weekend will these affect my tank? <It really depends on just how hot the tank gets. I would advise you to keep the tank very under populated and keep lots of oxygen in the tank with extra powerheads.> What are the temp. I have to have, I got that Big Digital Temp. alert, I would like your help so my fish wont have a hard time. thank you

Temperature Spike- Loss of Livestock 7/6/04
Hey There- You seem to be the end all resource here so I have a few questions for you.  I got home from work last night to find my reef tank a whopping 83.5 degrees.  
<hmmm.. the temp is not so terrible when the climb is/was slow. Many reef creatures can tolerate much higher temps. But in general, more then 2-3 F spike over a short period of time can be rough>
I added a frozen bottle of water to the tank to bring the temp down but it appears I have lost some livestock and everything in the tank looks ill.  
<a sharp drop can be equally stressful. Do note this for future reference. All good and bad things should happen slowly in aquaria <G>. The first thing to do in such cases is heavily oxygenate the water. Turn up venturis, add an airstone and/or add fans to blow across the tank. Improved O2 and slow temp reduction>
My LT Anemone hasn't melted but was found in the back of the tank with a lot of the mucous looking stuff in the trail of its path.  The cleaner shrimp was dead, and my goby, wrasse, and blue tang look like death has touched them.  I did an emergency water change this morning (20%).  
<excellent... when in doubt do a water change - agreed>
Is there anything else I can do to save my tank???  
<a few more large water changes in the next week or two>
I took the anemone out and put it into a hospital tank to see if it opens up again.  If not I think it shall be the toilet for him.  My live rock looks ill as well (the mushrooms and zooanthids are closed.)  What happened during the temperature spike-  The tank is normally 78.3??  Did the temperature spike cause an ammonia bloom????  
<more likely sudden oxygen deprivation>
Will a water change be sufficient to bring this under control or am I S.O.L.??  
<no worries... the tank can get right back on track. DO consider adding a fan to the timer for the lights, or run full-time if needed. It also would not be too expensive to add a fan to blow across the top of the tank plugged into a thermostat>
Thanks for you time on this matter.  Russell Sacramento, CA
<best of luck! Anthony>

- Dealing with Heat -
Howz it goin??  
<It's goin'...>
I have what could be a problem... I am living in Ottawa Canada, and our summers are VERY hot.  It was 34 degrees today, and my fish tank's temperature is currently at least 31.  First of all, will this be a problem. <Yes... it will raise the metabolism of anything you are keeping in the tank - most certainly will be fatal for corals. Fish can tolerate it for a while, but not for too long.> If so is there anything I can do to fix it. <I'd start by running a fan across the surface of the water... then, perhaps lighting the tank opposite daylight, to avoid heat build up... there are other options, but I would start here.> Thanx for the help.
Steve
<Cheers, J -- >

How much can they take? Temperature question.
>Hi, Hope all is going well there for you. I have a couple of questions for you. First of all, I live in south Florida and the temperature of my tank during the summer is usually 80 during the hottest part of the day (even with heaters off). Early in the morning when I wake up to go to work the temp usually drops to 78. Is this too much of a temperature change in about a 12 hour period? 
>>It's pushing it, but no, it's not terribly bad.
>Should I set my heaters to 80 so that the temp won't drop during the morning hours? 
>>How about this? I'll meet you in the middle at 79.
>Also, my tank is a 75 gallon F/O with 2 false perculas, 1 flame hawkfish, 1 royal Gramma and 1 coral beauty angel. I am thinking of adding a yellow tang in the next few days. I know he will probably be the most aggressive fish in the tank. Do you think there is anything to worry about as far as fights? 
>>No, I honestly don't think so with that mix. If you can make sure it's a smaller juvenile then you should be golden.
>Thanks for your help, James
>>Quite welcome, James. Marina 

How to handle a heat wave
>Hi all,
>>Greetings, my apologies for the late reply. Your email has been in another's folder and I just found it.
>I have a problem. I keep a 75 gallon saltwater tank with a 6" Volitans lion and a 4" Long Longnose Butterfly. I live in the southern US. Recently, the heat pump outside the house gave out. With temperatures inside the house climbing to over 100 degrees in the hottest part of the day, I am EXTREMELY worried about my fish. I have turned off the aquarium lights and directed a fan over the top of the tank that stays on all the time, but the temperature still climbs to above 86 degrees in the tank. With repair on the heat pump expected to take 2 weeks (!) and no local fish store willing to "board" my fish, what can I do? I work during the day four days a week, so a hands on solution is out.
Worried!!! Frank
>>You should have in place a system of fans to utilize evaporative cooling, along with an automatic top off for adding freshwater in order to keep the salinity stable. This can be quite simple, using gravity feed and a few 1gallon plastic jugs or soda bottles - you silicone in some airline valves and set the drip rate manually. Or, it can be a dedicated top off system with float switches, etc. Also, you can fill some plastic jugs (must have screw tops or otherwise be SEALABLE), those "Gladware" reusable, sealable plastic containers, or, in a real pinch, Ziploc baggies (I'd go with freezer quality bags, just to be sure), fill with water and freeze over night. Let them float in the tank for the day, but be careful with this method, as you could cause too much of a drop, which is harder on the fish than a rise. Let the temps stay around 80-83F if possible. Marina 

The Dreaded Heater Mishap!
>Dear crew,
>>Hello.
>First, thanks again for all of your hard work and patience. I am writing because I had a heater mishap, I must have turned the dial without noticing and the next morning the tank was up to 96 degrees!
>>It is not unknown for thermostats to become stuck in the "on" position as well. Sounds like you've got a bouillabaisse going there, eh? Very sorry to read it.
>Well, needless to say some things died (Coral Banded Shrimp, Mushrooms, and I think my purple Pseudochromis). Yellow Tang, damsels, percula, snails, and hermits- all OK.
>>Real bad, sorry to read this, mate. Glad you didn't lose the whole lot.
>I can't find the pseudo I think he must be dead inside a piece of live rock. 
>>Could be, or the hermits got a hold of his warm carcass.
>I can't think of a way to get him out if he is dead, because he gets in the smallest of holes. 
>>As those Pseudos are often wont to do.
>1) Do you have a suggestion of a way to maybe get his little body out?
>>No.
>2) If not, how long will this affect my cycle?
>>This depends on many things, but you can certainly boost it with Bio-Spira. This is the good stuff <opens trench coat> right here.
>3) Is the best thing to do is just frequent water changes if I can't get him out?
>>Yes, and do them anyway. You may need to do one or two really big w/cs - on the order of 75%-100%. Make sure you've aged that water at least a full day, two or three are better. Match everything, as I'm sure you know. Oh yes! Be SURE to bring your tank temp down slowly! No more than two degrees Fahrenheit/24 hours.
>Thank you so very much.
Sincerely,
Keith Tallbe
>>Again, so sorry to hear this. Get that Bio-Spira first thing, then mix up the water anyway (it's always good to have on hand). Best of luck, and if you don't have a hospital set up, be prepared. This sort of thing may spur on some stress-induced troubles. Marina 

Fish Heater 4/27/04
I am currently doing a project involving testing a material found in the knee.  To do this, I must have the material be body temperature (98 F).  
I thought of using a fish heater to heat the water that the material will be placed so the material so the material will be at its normal temperature.  I was wondering what fish heater you would recommend using (should be 100-150 watts) and how might I go about tweaking the heater so it can reach that temperature.  Also, if you can give me the names, email, URL, and phone number of their manufacturers, that will be greatly appreciated.  Thanking You, ~Huma
<Hi Huma.  Most aquarium heaters aren't designed to heat water to such a high temperature.  If you have to get all the way to 98F, you may have to use some kind of lab heater on a temperature controller.  Ebo-Jager heaters will heat up to 94F.  Won Pro-Heat titanium heaters go up to 93F.  I found these products and their specs by doing browsing www.marinedepot.com.  You could also shop here: http://www.drsfostersmith.com/product/shop.cfm?N=2004&ref=wwm&subref=AA  Dr. Fosters and Smith is a WWM sponsor, and we always appreciate support of our sponsors.  Best Regards, Adam.>

Temperature Issues 
Hi-I have two issues with my tank....One is how can I keep temperature control? My tank is 20 gal. and the water heats up really fast in this sunny hot weather. I can't tell if I keep getting new ich blooms w/ this ever changing water climate (my tank has been running fallow for a few weeks now). I am just worried that w/ the new fish I will put in the tank soon and w/ this hot weather, that I am gonna keep getting ich outbreaks.<I would take off the top and point a fan or two at the surface, if needed cover the top with screen to prevent fish from goin carpet surfing. Also I would let the tank go follow for at least another month to be safe.> The other thing is, I have a turbo snail, and I noticed the other day a baby snail. I thought that turbo snails did not self re-produce, is this true? I don't want my tank to be over run w/ snails-one is enough for my small tank. What should I do about my snail problem?<The snail probably came from some live rock or the like.> Thanx for your help, I love this website!!!! Heather.

- Summer is On The Way -
Hello,
My reef tank temperature is running hot I think.  It averages about 82 to 84. <That is a bit warm... much warmer and you will begin to lose some of your corals.> All the life in the tank is doing well but it is just the beginning of summer and am concerned. <You should be.> I happen to live in Phoenix AZ so heat is always a problem.  I am wondering what if anything i should do all the lighting is elevated about 2 inches above the glass top. <Start by blowing a fan across the surface of the water... this should lower the tank temperature a bit... if not sufficient you might want to explore having the tank lights on in the middle of the night or perhaps a chiller.> so i know that that is not a problem but still.  
Thanks for your advice
<Cheers, J -- >

- Heater Scale Deposits -
Dear Crew:
Thanks for the great site. I am new to marine aquaria. I have two large tanks, 75G and 125G, which I maintain similarly and are 9 months and 6 months old, respectively. Both have 300W submersible heaters. I found a heavy scale on the heater of my 125 a few days ago.  How long it has been there I am not sure but there is no similar scale on the heater in the 75G. Here is a picture of the scale in the 125G:
It is orange-brown and has spalled in places taking away with it the decorative glass-stenciling. I am interested in what caused the scale to form because I am trying to track down the cause of a prolonged micro-algae or phytoplankton outbreak in this tank. <They are not related.> The calcium levels in the two tanks are similar (around 500 ppm) but the temperatures are different: about 75°F in the 75G and 83°F in the 125G. Possibly the higher temperatures or longer "on" times could have promoted scale formation in the 125G, but I was also considering another possibility. I thought that the scale formation might be due to my having left a floating glass-cleaning magnet in the tank for two-weeks. <Nah... doubt that. The scale is simply just the product of a high calcium level and the temperatures of the heater right at the surface of the glass.> I had seen other people leave them in their tanks but I took the magnet out after the algae or phytoplankton outbreak because I thought iron might be leaching from it. <Not all magnets are made of steel...> I had difficulty controlling the outbreak but eventually managed through water changes, improved skimming and use of a canister filter. Do you think that increased iron levels could lead to a runaway algae outbreak and produce the scale on the heater? <No... that is just calcium and very normal for just about any accessory attached to a marine tank and not regularly cleaned.>
Respectfully,
Karl
<Cheers, J -- >

Ick, heat and lights
Hey,
<Hi>
How long would you let a tank go fallow that had an ick breakout? Is three weeks enough?
<I would aim for 4-5 weeks, just to be on the safe side (however, the normal ich cycle will last around 3 weeks depending upon the temperature of the aquarium.)>
I am having trouble with rising temperature. Early in the   morning my tank is around 74 degrees. The lights go on for 8 hours. At the end of the eight hours the tank is 78 degrees and that seems like a big temperature change to me. Are PC's considered heat hogs?
<They can be if you do not have proper ventilation>
I have a 96Watt Coralife PC on a 40 gallon reef tank. I have a glass top but I keep the lid cracked and I have a hang on the back filter so the tank should get enough air, but maybe not. What do you think?
<Because the temperature seems to raise while your lights are on, I'm thinking this heat problem is due to the lighting rather than pumps creating extra heat. Adding fans to your canopy should help out a lot. If you have a glass lid over your aquarium, you may want to consider removing that because it's most likely trapping heat in your aquarium. May I ask what the room temperature is during the day?>
My friend wants to do a 20 gallon long mini-reef tank, but he just wants mushroom corals. I have been successful propagating mine and will "sell" him a few rocks, lol. What lighting do you recommend if he is just doing mushrooms, i.e. reds and blues?
<Whichever Kelvin temperature your friend likes best. Mushrooms will do quite well under a wide variety of spectrums.>
Can he get away with a 30" fluorescent or does he need to get a
24 inch, 65 watt, PC? The PC is more than twice as much! It is also $19.00's more than a double bulb florescent. Which of the three would you recommend?
<For best coloration and growth of the mushrooms, I would highly recommend the 65wt power compact.>
Thanks.
<Take Care, Graham.>
Nathan West

Lighting Cycle for Algae and Heat Issues?
>Hello,
>>Hello.
>I started my refugium with Caulerpa around 2 months ago and during that time I had my two 65-watt power compacts on 24/7.
>>No need to light 24/7, my friend.
>About 3 weeks ago I removed the Caulerpa and replaced it with a good sized piece of Chaeto using the same amount of lighting.
>>Amount AND duration?  Again, no need.
>During this time the Chaeto is growing like crazy which is a good thing and my nitrates have been a constant 0.
>>Low nitrate readings are indeed a good thing.
>The bad thing is my water temperature is varying a couple of degrees throughout the day due to the heating from the power compacts.
>>Not really, a couple of degrees is certainly tolerable.  I will ask you one thing, and it's the most important thing: do any inhabitants in the display show ANY negative reaction(s) to the slight change in temperature?  Many folks get so caught up in monitoring parameters that they forget to simply use their own powers of observation, which are often much better than they realize.  
>My question is do I still need to have the lights on 24/7 for the Chaeto?
>>Not for either.
>If not what would be a good cycle to use? I have heard that a good scenario is to have the refugium lights on opposite of the main tanks.
>>Only if you're having big pH shift issues is that necessary.  With my own first system I devoted a full 1/3 of it to Caulerpa, which meant that it was lit when the corals were lit.  I had NO problems whatsoever.
>If this is the case should I gradually switch to that timeframe or will an immediate effect
not cause a problem.
>>I don't think you'll cause the algae any great stress should you decide to go this alternating cycle, it's not got a nervous system with which to react to such changes.  Plus, if you think about it, many of the animals we buy come quite literally from the other side of the world.  The time zone is quite different, and after a period of adjustment, they can fare quite well.  This would be even more true of algae.
>My concerns are if I turn the lighting time down I will get nuisance algae growth in the refugium.
>>With no excess nutrients you shouldn't.  Nitrate would not be the only issue, of course, but this is part and parcel of WHY you are growing the macros, isn't it?  ;)
>Thanks, Tom
>>You're welcome.  Marina

Trying to Find a Balance
>I have a 40 gallon breeder tank with JBJ 192W compact fluorescent lights, glass covered top, and a JBJ 1/10 chiller. The tank fluctuates between 76.5 at night (no lights) and up as high as 79 in the winter and in mid 80's in the summer. I have the setting at 77.7 right now which chills 1 degree below that (76.7) and kicks on 1 degree above that (78.7) should I allow it go get warmer before the chiller kicks on say 79.7? My house is a ranch with a bonus room above the garage. Its warm year round up here! I want the tank to be the right setting while also being as efficient as possible. I am afraid with the setting too close together it will stress the fish. What do you recommend? Thanks, Rob
>>I recommend that you keep the temperature within as tight a range as possible. Large (defined as being +/- 5F) temperature swings are MUCH more stressful to fish than most folks realize (especially downward). I'd set things up to keep the tank between 77-80F. Marina

Titanium & Electricity (12/17/2003)
Hello Good friends! <Hello to you"
Can you all tell me if one needs to use a grounding probe.. (titanium) if one already uses a titanium heater? Does the titanium heater double as a grounding probe? Boy could I use just one more outlet! <It will not work as a ground because the titanium case does not have any direct connection to ground and the heater is plugged into a live wire. If you need the outlet, get a 3-prong multi-outlet extension cord or power bar. It's the third prong that is the ground on a probe; the other two are non-conductive (plastic)>
Also, my titanium heater seems to have my fine aragonite sand baked onto it??? <I have a hard time seeing how this would be a problem or danger, but you might try wiping in off. You could also contact the manufacturer and ask them what to do.> Any help would be appreciated?
<hope this helps, Steve Allen>

Heater problems
I recently received a response about some heater issues that I have been having. Here is the scoop, I have a digital thermometer that I've calibrated at my LFS. My temp in the tank has episode were it fluctuates throughout the day. Usually it stays around 78 during the day and drops down to about 76 at night, but on more than one occasion I've woken up to find either my temp lower or higher than my heater is set at. In my latest incident I woke up this morning to find my temp at 81.5 and my heater is on!
<yikes>
Its only set at 78 and it is practically a brand new Rena cal. What is the deal? Should I move it out of my sump?
<if the temp is the same in the tank and in the sump, No>
Is my heater malfunctioning?
<sounds like it>
    What do you know about the titanium heaters with the digital controls?
<love them, use them all the time MikeH>

One Hot Clown Trigger!
Hey, I have got a clown trigger (3in) in a 55 gal.
<Larger quarters in the future? Please say yes...>
Yesterday my heater spazzed out on me and the water got really hot, probably 90-95...really hot to the touch.
<Yikes!>
My Koran angel, yellow tang, and 4 stripe damsel all looked fine still, but the clown trigger was breathing very rapidly and having trouble swimming.  Once I noticed the problem, I took out 5 gallons of the tank water and switched it with 5 gallons of cold water and removed the heater, this cooled the water down a lot, for the past 14 hours he has been under a piece of my live rock, still breathing heavily and not moving around, his coloration is almost entirely black-the yellow is very dark, and the white spots are dark as well.  My biggest worry now, is I noticed that his eyes seem cloudy, and maybe bulging( I can't really tell because of his location) He is not eating, or swimming at all, but the other fish still eating and behaving normally. So, my question is, should I remove the trigger and treat him in a doctor tank, if yes then with what? And is there anything else I can do?  Thanks a lot
Eric
<Well, Eric- first of all, please perform any and all treatment in a separate aquarium. It is hard to say exactly what this guy may be suffering from. Some of the symptoms that you are describing are similar to those which accompany bacterial infections. However, many times, these maladies can be corrected with very simple means, such as maintaining very high quality water conditions (use aggressive water changes, protein skimming, chemical filtration media), and overall stability. Removing the fish to clean stable quarantine conditions could make a big difference. I'd try this and see if any improvement occurs. Otherwise, you may need to utilize an over-the-counter antibiotic (once again- this assumes a bacterial problem) once you confirm what you're dealing with. Finally, I do once again want to urge you to provide a larger aquarium for your specimens. Both the Clown Trigger and the Koran need a lot of water volume and sheer physical space, both to ensure long-term health, and to dilute their substantial metabolic wastes. Keep a close eye on things, and tweak as necessary. Good luck! Regards, Scott F>

Busted Heater, toxic bucket?
Hi Bob,
<Hello Joyce>
Joyce Mahoney here. Long time no see. Are you going to the MASLAC X-mas party at the Queen Mary??
<Not planning on so at this point, but maybe>
I am going to try to attend as I have not seen anyone for some time. I had to stop going to the Friday night meetings as they are too far from my home and the Friday night traffic going into Los Angeles is brutal.  It seems that on Friday night the last thing I want to do is hit the freeways about 5 pm to go to the meetings!!! I hear that next year they will change the day to Saturday. Should be better.
<The traffic IS a MAJOR determinant in my going anywhere as well>
I have a quick question for you. Yesterday my glass heater broke in my water makeup barrel. I am wondering if the blue plastic barrel and the mixing pump are ok to use?
<Should be fine. Just give them a freshwater rinse>
  I do not think the heater was on at the time it broke. I went to use my water and found the broken heater, but the circuit was not tripped, so I think it just got knocked by the pump and broke. I emptied out the water and glass from the barrel and rinsed the barrel and pump with clean water.
<Sounds good>
I am thinking it is OK to reuse the barrel and pump, but I thought I'd ask your advice.
Hope to see you soon,
Joyce
<Be seeing you. Bob Fenner>

DOH! I Broke the Thermometer, Now What? 
>Hi Bob and team. 
>>Hello, Marina tonight. 
>I'm afraid I've had a disaster in my 200 gallon reef aquarium. While recently double checking my chiller reading, I stupidly left a thermometer in my sump. I found it this morning, broken at the pump intake. 
>>Oh my, thusly the term "disaster". It's not as disastrous as you think, though. 
>The lead balls have been sucked into the pump and the mercury is gone. 
>>Not mercury anymore, my friend, usually alcohol (with a dye) is used in modern thermometers. 
>Everything in the tank looks OK so far (corals and fish), but I can't imagine that'll last. What should I do? I'm sure water changes, carbon and PolyFilters will help but I can't imagine I'm ever going to find the lead balls? 
>>No, I don't imagine you will, either. But I wouldn't expect such a small amount to be a very big problem in the short or long run anyway. If you're very concerned about the contents, contact the manufacturer, but to the best of my knowledge the potential for mercury would be the biggest issue and as far as I know it hasn't been used for quite a few years. You're correct, water changes, carbon, and PolyFilters will help, though I don't know at all how readily lead actually dissolves in water (thinking of wrecks of Spanish galleons and all the lead shot/balls they find, all encrusted with stuff). 
>Any advice you can give would be great. I hate the thought of tearing down my tank and starting again. Dave. 
>>No, no, no, I really don't think you'll need to go so far. Between the water changes and the chemical filtration you should be able to deal with the small amount of dye released. For "next time", get a bit of clear plastic tubing, the kind used for undergravel filter lift tubes, along with caps. The caps can be the same clear plastic, or PVC that fits. Glue one end (I'd use Superglue-cyanoacrylate) on permanently, leave the other so you can slip it on and off. Drill some holes in the tube, and it will protect the future thermometer from such terrible mishaps. Marina 

- Heater Won't -
My Jalli 500 watt heater keeps quitting on me. <That's not good.> I have a 90 gal tank with a 20 gal sump, the heater is in the sump, has never come out of the water while plugged in, is not covered by anything, the control head is properly mounted and connected, temp probe is in the middle of the tank.  I just got the entire heater replaced 4 weeks ago, under warranty, because of the same thing. <Nice to see they're batting 1000.> Is this a cheap heater? <I'm not a huge fan of Jalli, but I know someone who is and swears they [Jalli] try very hard to get past problems like this. If it were me, and I'd had two heaters broken, I'd ask them to buy me a new heater. There seems to be a flood of heaters with electronic controls coming from Asia... I think each one needs to be well tested before tried on your main tank as you might be in for a surprise.> Would I be better off with 2 -250 or 350 watt units? <In the cold parts of the country, I would suggest having two 350's with one set a little lower as a back-up should the main one fail. With larger heaters, they tend to be 'on' less often, can heat a given volume of water quicker and I think [in my own weak non-scientific study] they will last longer. Any under or exactly-sized heater that is 'on' all the time will break eventually, regardless of brand - is just my observation, but have seen it happen often enough.>  I do have a 250 watt backup working now, it struggles to keep 78 degrees. <Using two 250's would guarantee the failure of one, and then the other.>
Chilling here in Pa, thanks... Mike
<I believe it. Cheers, J -- >

Keeping Stable Temperatures, Or "Just Chillin'" 
>Good Morning Crew; 
>>Good evening folks. 
>Now that the weather is changing and the outdoor temps as well, what is the best way to stabilize the temps in our aquarium (75 gal)? During the summer months and having the house a/c on the temps were good and into the early fall. We have had this sudden spurt of warm weather but not requiring a/c, the temp in the system is running 79.3 - 80.5 digital. If I keep the doors on the base open it will come down to maybe 77 or 78. 
>>Not knowing what you're keeping, it seems to me that as long as whatever it is is tropical, you're WELL within acceptable limits. 
>Have checked the heaters and they are functioning fine, set at 70 one at 72 (one in tank, one in sump). Do you need to have a small chiller to run with the heaters in the winter when the household heat comes on? 
>>Folks use chillers in conjunction with heaters to keep tank temperatures within very tight parameters, this is considered a year-round issue. If this is what you wish to do, then a chiller would be the best route. 
>I usually like to run my tank around 76-78F maximum. This is our first fall into winter for our system, having set it up in February of this year. Thanks once again, have a great weekend. 
Ceil Wagaman 
>>Thank you, yourself as well, and you're welcome. Honestly, though, I would think that hitting a high of 80F isn't much of an issue, but if you feel more comfortable keeping tighter parameters, as I said, then a chiller would be the most precise method. Marina 

Tank Temperature 10/8/03
I have had all kinds of advice on tank temp. Anywhere from 72 f to 78 f. What temp do you prefer? And what temp would you recommend for a 40 gallon reef tank with 3 fish and lots of coral? My current temp is steady @ 75 f. Thanks, Jason
<the water temp depends on what you will be keeping. Freshwater or Saltwater, and fishes from what region? In general though... 76-78 F is a good range for most tropical species. Anthony>

- Specific Gravity & Temperature -
Hi, Hope all is doing well there.  I have a 75 gallon F/O tank.  My fish are:  2 percula clowns, 2 lemon butterflies and 1 coral beauty angel. Please tell me what you recommend for tank temperature and specific gravity.  I have been keeping the tank at 76 degrees and the specific gravity at 1.021.  Thank you, James
<James, I'd shoot for 1.025 for salinity - it's what the ocean is typically at. As for temperature, you could go a little higher, but there's nothing wrong with 76F - 76-78F is ideal.
Cheers, J -- >

- Temperature Variation -
Hi
Greeting from Singapore !
I recently started a Tropical Marine Fish Tank, this is what I currently have:
2ft tank - I assume at least 50litres of saltwater.
I am using Chemipure and ceramic rings as my main medium for filtering and I have the following.
4 damsel
1 clown fish
1 cleaner shrimp
1 boxer shrimp
1 slug
2 camel shrimp
What I would like to check is whether my tank temperature which varies between 28 to 30 degree Celsius alright for my fishes? <Not really, in the short term it's probably ok but in the long term, you probably don't want a variation of more than one degree Celsius in any given day.>
Can I put in anemone with such temperature or should I use a ventilation fan to bring down the temperature to 27 degree Celsius? <I'd work on bringing the temperature down for everything in your tank, but the more important factor for anemones is lighting... you need really intense lighting to keep an anemone.>
Your guidance and advise is very much appreciated and please reply me via email as well.
Thank you
Terence
<Cheers, J -- >

- Temperature Variation, Follow-up -
Hi
Thanks for your prompt reply <My pleasure.>
So, is it ok even if I leave the temperature alone which usually stay between 28 to 29 degree and only during certain month it hit 30 degree Celsius? <Yeah, I think that's ok.>
When you said short term...what does it mean ? one month ? <Something like that - it's just that 30C is really higher than is healthy for your animals. Sustaining them at this temperature for more than a couple of weeks will increase their metabolism and foreshorten their life span - also lessens the amount of dissolved oxygen, so all in all... the ideal temperature range is 24.5 - 25.5 Celsius.>
Cheers
Terence
<Cheers, J -- >

- Temperature Variation, Follow-up -
Hi
Thanks again... but even with the fan on, the temperature I hit the lowest is 27 degree Celsius. Is that ok or would it better to let the weather determine the temperature? <In your case, I think trying to keep the temperature as close to 25.5C is best... so if it's 27C, then so be it. It's not ideal however, but much better than leaving things up to the weather.> My tropical tank is always around 28 to 30 degree and I see that they are still swimming happily. <You may have noticed that they are breathing rather fast - because fish are cold-blooded animals, their metabolism is regulated by the temperature of the water around them. They can survive at higher temperatures, but their metabolism runs faster... and will eventually shorten their lifespan.>
Would it be better if I turn on the fan only when it hit 30 Celsius to bring it down? <No, much better to keep things as steady as possible, as well as on the cooler side.>
One more question, must I get a anemone for my clown fishes and what is it purpose? <No - in the wild, they protect each other, have a symbiotic relationship. In captivity, clown fish can do quite well without one. Anemones are not easy to keep, and require high intensity lighting to thrive. This same lighting will create more heat in your tank, and I can assure you at the temperatures your tank is running currently, an anemone would not last for very long there.>
Apologies for all the questions, just that I am a newbie where marine fish is concerned.
<Consider reading some of the articles that make up Wet Web Media, we answer questions like this all the time and archive them for your perusal. Here's a good place to start:
http://www.wetwebmedia.com/marine/inverts/cnidaria/anthozoa/anemones.htm
http://www.wetwebmedia.com/temp_faqs.htm >
Thanks
<Cheers, J -- >

Tank overheated, everything dying!
>Hello All,
>>Greetings, Andrea, Marina here.
>I live in Northern California and we had a heat wave that lasted about 4 days last week.  
>>Indeed, I have a sister in Pleasanton, it can be most Unpleasant.
>I have a 100 gal tank that got up to the high 90's a few days ago, stayed there for about 2 1/2 - 3 days despite everything I could do (while freaking out) and then dropped back down to its normal temp of around 80 degrees.  
>>Even setting up fans to blow across the water's surface?  That can usually keep it relatively under control, unless you're in a terribly humid place.
>Enough water evaporated to bring the salinity off the charts, even with constant water changes with ro/di fresh water.  
>>I am unclear here, did you top off with the RO/DI, or did you perform water changes with fresh saltwater *made up* with RO/DI?  If you did the former, the salinity should NOT have swung like that.  If you did the latter, you have learned from your mistake (and so will many others).
>I flushed my colt yesterday after moving it to a 5 gal nursery tank (it was sloughing off large amounts of purple ooze before it died) and I flushed my scissor tail.  I can't find any of the other fish except the clown because he won't leave his anemone (which doesn't look that good either).  Is there any chance any of the following fish will re-surface alive: coral beauty angel,
mandarin goby, scooter blenny, red and purple fire gobies?  
>>I would begin moving things about, as well as performing tests to deterring how much of an ammonia/nitrite spike you have.  This can tell you quite a bit as to how much die-off you've experienced.  FYI--many of the invertebrates you've listed *should* have been able to survive the temp spike, but few will survive large swings in specific gravity.
>Also, can a devil's hand survive that kind of water and salinity fluctuation?  How about a sea whip (gorgonian) or a Montipora capricornis that is starting to bleach?  
>>Truthfully, your own observations would answer this better than I.  I could say, "No, they won't", but I've known many who have suffered similar and survived.  I could say, "Yes", but have known many that didn't survive.  WATCH.  
>Some of my mushrooms seemed to have partially melted.  Is there any chance they will come back?  
>>Not the "melted" ones.
>How about the star polyps that have retracted?
>>The stars would be most likely to survive, but you really do need to ensure you've got proper salinity, not just temp, and do HUGE, frequent water changes this week.  
>I appreciate any advice you can give.  I am off to tear apart the tank now to try and find the lost fish and discard anything dead.  Maybe I should take the tank down and just stick to diving, I am so heartbroken.  
>>Well, we don't want that, and, if I recollect correctly, a dive computer's cost just about equals that of a good chiller.  I do hope this helps, try to get everything that's dead OUT--ASAP.  Remove the rock, frags, gently flush with saltwater to remove dead, dying, and debris before replacing into the tank.  Large trays (like cat litter trays) are helpful to have around during this process, just for holding while you're cleaning up.  Also, do join your local club, you wouldn't BELIEVE how many people will step up to the plate to help out with cleaning out, restocking, donating frags and the like.  Same thing goes with many of the internet boards, such as our own at http://www.wetwebfotos.com/talk .  Best of luck to you, Andrea!  Marina

Thermostats for Fans, Chillers, Heaters
Hello guys, Can anyone tell me where I can find an adjustable thermostat with a submersible temp probe that I can
Connect my cooling fans to. THX, Wayne.
<Sure Wayne! Surf over to one of our fine sponsors and look at the single and dual stage therms for heaters and chillers. The single stage will run either a heater or chiller and the dual stage runs both a heater and a chiller. Either will work for your application, just plug in the fan instead of the chiller. They are a bit spendy, but worth it!  Make sure you tell them we sent you! Have FUN! Craig>

Question on my reef tank
Hello i have a Visi Therm fully submers 300 watt heater is this sufficient enough for my 75 gallon tank? i set it to 82 and it has gone up one degree in the past 3 hours is that right this is brand new so i guess it worked right its gone from 80 to 81 in 3 hours?<This will be fine 82 is a little high though, I would do more around 78.  Cody> thanks JM

Ice Probe
<Good evening, PF here with you tonight>
Hello Crew, hope you all are doing well.
I have a question about those little Ice Probe thermoelectric chillers, the one you can stick through a bulkhead and bring down a 55gallon tank 12 degrees, according to the ad.  I have a 90 gallon that I would like to drop a few degrees, would it be possible to use two of these to do this?  I already have two muffin fans in the canopy for cooling the halides, they are really no problem.  But my Velocity T4 pump and the in sump Rio2100 for the skimmer are major heat producers.  I don't want to run extra fans over the sump for more cooling by evaporation (I don't have an auto top off ) it might have a negative effect on my salinity. Right now the tank is running without lights ( it was just set up ), and it is hovering around 82 - 84 degrees!  The house is only around 76 degrees, cooled by central AC.  What is your opinion?
<Well, you can also place them in small HOT (hang on tank) filters, I've seen that done (and offered on EBay that way). You could also bite the bullet and buy a chiller, it would insure better temperature regulation. You can find them for decent prices, it does take some searching though. I would also recommend reading this: http://www.wetwebmedia.com/temp_faqs.htm >
Thank you.
<Your welcome, have a good night, PF>

Overheated tank
>Folks,
>Thanks for your advice to be patient following the stuck-on heater episode.  As you said some marine organisms are hardier than we think. All the fish survived the temperature rise to over 95 degrees F (I don't know how long it had been at that). In fact I was adding a little brine shrimp when I realized all wasn't well and the yellow tang (added only two days earlier) fed as if nothing was wrong.
The blood shrimp, assumed to be dead, emerged from the rock two days ago and seems fine. One finger coral remains bleached and closed, but then it never opened anyway. The cup coral looks a little worse for wear, but is gradually opening.
Strangely the other finger coral, about which I wrote to you the day before the heater stuck because it never opened, has been 'fully polyped' since the time the water cooled down, nearly a week now.
The star polyp colony has slowly opened, but the polyps are much smaller than before, and a brighter green. Previously they were a creamy brown, and only showed green under actinic blue light. Any ideas?
>>Has to have something to do with the zooxanthellae, I would assume.
>So the only definite losses to date are two cleaner shrimps.
>>Not too bad for almost poaching everything, eh?
>Thanks again for your help Brian
>>Well, it wasn't me who helped you, but whoever did will be quite happy to know of your success.  Marina

Stability Is The Key...
Hey guys, I had two quick questions.  First, what temperature should I keep my tank, which houses a Humu and a damsel.
<I like a temperature of 76- 80 degrees Fahrenheit...Stable temperature is more important than any one specific number, IMO>
My other question is that I have some sort of reddish dots/algae on the glass that I am not able to scrape off successfully, do you have any clue to what it is?  I do 25% water changes weekly.  Thanks a lot, Jon
<Well, Jon- it sounds like some sort of algae or diatom...Hard to be specific without seeing it. However, it's a safe bet that, if you continue to exercise good husbandry (such as the water changes, with high quality water), and utilize various nutrient export processes, than this possible nuisance algae will go away. Good luck! Regards, Scott F>

Tank Temperature
Wanted to ask your opinion. . . I have a 200 gal.. FOWLR tank with one Naso Tang, two smaller yellow tangs, one maroon clown, and one Australian Lime Green Wrasse. <Very well, Paul here to do my best>
The temperature is a steady 80 - 81.5 degrees (I live in Florida).  The fish seem to be doing great (and have been for two years at this temp) but recently someone told me that the temperature was too high.  What is your opinion? <Well, I subscribe to the technical aspect. Look at the published reports and data that is available related to the area where your animals typically inhabit. Then do your best to meet in the middle ground of the average temps. My understanding is that based on the area of where your fish are collected I think I would subscribe to the average temp of 78-80f without worries. You choose which range of the one mentioned you want to employ.>
I am planning to add two Hagen 802 powerheads inside the tank for better current. . . will this increase my temperature significantly? <Maybe a degree or two. Keep an eye on it> If so, any suggestions on lower the temp without having to purchase an expensive chiller? <I don't think you need a chiller. Lower the temp to around 78 degrees and add your power heads. Keep an eye on the temp for a few weeks.> I just can't afford it right now. <No need for a chiller for your set up, unless your temp changes with atmospheric changes during the heat of the day. Being that you are in Florida I wouldn't be surprised to hear that you use an air conditioner to regulate your house during the day. Keep the house around 78f but in any case I would put the chiller out of mind. Ron Toonen has done a great deal of research on tank temperature and salinity in reference to the actual reef environment from where our inhabitants come from. Do a search for him on in your favorite search engine. The great heat and salinity debate is on!!!!>
Thanks for your help, <Thank you for coming to our site and contributing. Paul>
Elizabeth

Coral reef tank temp.s
In reply to a woman living in South Florida, where temps get to the 90's during summer, you wrote:
>>>For "disastrously warm" days (where the water is getting over 85F.) floating a previously frozen milk jug of ice can save a system... for emergencies only...
And otherwise, just allowing the system to get warmer (low to mid eighties F.) is generally not a big problem (a little more maintenance) for true tropical set-ups (same old reference to coldwater organisms that are sometimes sold as warm in the trade... avoid these...)
Bob Fenner<<<<
I have a 55 gallon semi reef tank (will be adding Acroporas shortly and had a few questions)...15-20 gal sump and 10 gal refugium I live in HOT HOT HOT South Florida.  Temperature inside gets to a swelling high 80's to 90 degrees without a/c.  Roommate wont tolerate a/c on over 83 degrees.
My tank cooks at 86-87 when the house is 83
<Maybe this time of year you can/should switch your lighting period to more in the cooler evenings... doesn't matter to your photosynthetic life if the period is adjusted over time>
Chiller is connected and I'm looking for a stable temp of 82 rather then fight over the issue and drop the temp in the house down to 75 so the tank could be 78.
Is 82 degrees +/- 1 degree (stable) ok for a reef?
<For the vast majority of the species kept by aquarists, yes>
Am running two 96 watt PC's (mostly dull, barely fluorescing semi actinic bulbs, and one 250 watt 6500k Iwasaki); 3" cooling fan connected to canopy, blowing directly across the halide (super flow rate of over 500cfm easy); sump is open with plenty of circulation, refugium unfortunately is in a separate cabinet 2 feet away from tank (higher than sump so water is gravity fed back to sump). with refugium lights on 24/7 ecosystem method-miracle mud/Caulerpa, etc.. so some heat generated there with the 20 watt bulb, but cant be much.
<Not much>
Chiller is a Teclima RA200.  Water from sump to chiller at a flow rate of 150gph (i feel slower is
better?. contact time with coils should be longer no?)
<Actually... the flow rate being higher will result in the most cooling>
The folks at Teclima (in Italy) say min flow rate should be 105 gph yet the folks where i got the chiller say 400 gph is about right.  LOL   Imagine trying to cool water that's whipping by coils at 400gph?
<Think about this... the "draw down" (removal of thermal energy is a function of the overall mass, input and contact time... on the extreme opposite viewpoint (no flow) how much warmer would the system water be?>
I told the people there that I have a 55 gallon, with 20 gal sump and 10 gal refugium. MH and PC lights, and tank is about 87 degrees when no a/c is on in the house.  Asked them what flow rate would be most energy efficient to run thru chiller.  They were clueless, but I'm thinking. slower is more efficient than faster, no?  Contact time with coils = cooler water exiting chiller.
<And warmer/est water elsewhere... You can likely "do an experiment" here that will satisfy your curiosity. Try running the flow rate at both the 100 and 400 gph levels... on different days, graph the temperature results...>
You stated "low to mid 80's" to the Florida woman, regarding her reef.
<Yes>
I'm trying to set my tank up with Acropora/Montipora, and am wondering if 82 degree temp via chiller is ok.
I really cant lower the temp anymore than that, or I'd have a blow out fight with my roommate who is the cheapest SOB on the planet when it comes to electric bill.
<You can/could calculate or directly measure how much power the chiller (whole tank) is using and offer to pay for it yourself>
He states , "that's YOUR tank, not mine". yet he shows it off to all his girlfriend's when they come over and introduces it as "our tank".
<Human nature.>
Time to bury him under the Deep Sand Bed, methinks.
<Make your peace with this trait, try to change it, or seek a new living arrangement>
Regards,
Steve
<Be chatting, Bob Fenner>

Reef temperatures
Dear WWM Consortium:
<Craig here today...>
55 gallon all glass tank, with 20 gal sump and 10 gallon refugium; currently FOWLR setup and adding some polyps and mushrooms; and now Acropora/Montipora SPS corals higher up near the halide.
I have two 96watt PC's and one 250watt 6500k Iwasaki MH bulb (no, I'm not making lava. have fans and a Teclima RA200 chiller).
<Hmmm, not out of line to me! I'm running 2 - 175 watt 10K's with two 110 watt VHO actinics on a 55 and it could be 2 - 250's depending on how deep I wanted to keep clams/SPS and placement above tank/light needs of those closer to surface.>
My query is the following:
My roommate is a cheap SOB and wont chip in to run the air conditioning in the house.  I live in South Florida and inside it can get up to 90+ degrees when the windows are closed and no one's home for a day or so.
<Phew....I'm sweating just thinking about it....I'll be right back, I'm gonna go shower....>
My chiller claims it can drop a 55 gallon tank down 20 degrees.  I figure my total system water volume is around 75 gallons or so, due to rock displacing some of the water.  Thing is, I'm going to beg my roommate to set the a/c on like 83 degrees in the house this summer.  
<Does he run it at all?  You know, I would figure the cost of powering the darned thing and pay the extra myself to not die in a pool of my own....anyway, I would do the math on how many KWH the thing uses (it can't be that much) and try that.  Once he's cool he won't be such a em...hot head.>
In your opinion, is it more important to keep the reef from fluctuating 2-5 degrees+/- daily, or to have a constant temp of say 82 degrees?
<Same thing, no? Steady at a set point is the same as not fluctuating. It is going to fluctuate some, depending on size and efficiency of heaters or chillers. If you can get it to stay around 80-82F you have no worries my friend!>
Believe me I'd love to have the tank at the textbook 78 degree mark, but that'd mean reducing the air temp in the house to around 80...and heaven forbid I did that.
<Depends on the textbook. I don't need a chiller, fans are fine in my area, but my heaters are set at 80, and actual is 78.7-80F winter and 78.7 - 83F with a spike or two to 84-85 on the hottest days of mid-summer with no noticeable ill effects. The average temp in the tropical oceans of the world is around 84. If you can get 82, I would relax.>
So I'm looking to strike a happy medium here, where the house a/c is basically on "life support", allowing us to breathe somewhat cool air (yes 82-83 degrees is DEFINITELY cooler than the brutal summer 90's we get inside this place). Would it be ok for my corals to live in a CONSTANT temp of 82 degrees?
<I don't see a problem, provided all other params are within the norm (water quality, changes, skimming, etc.) It *will* fluctuate a bit from there just from calibration and capacity of the chiller and thermostat, but I wouldn't worry about 82. I'll bet you will actually be able to keep it lower with an 83F house, and maybe down to 79 or so at night. Some fluctuation is going to happen.>
I've visited so many reef sites and read that folks keep their tanks in the 80-82 degree range with little/no problems with their corals dying off due to high temps.
<You mean temps higher than 82? Doubtful 82F was the causative factor, otherwise many of the worlds reefs should be dead!
Hmmm, and all of my corals too!  Not to worry my friend, 80-82 is perfectly acceptable. Do endeavor to keep it from spiking much higher though...>
What are your thoughts? (besides killing my roommate and burying him under my DSB)  regards, Steve
<That would foul your DSB Dude. No, best to turn on the air, buy plenty of your favorite cool, refreshing, beverages, put the ice chest near the tank (you want it on ice) pull up a couple chairs, and enjoy with your friend. How can he not come around then?  Have fun!  Craig>  

Temperature Fluctuations
Greetings all, firstly let me express my true thanks for all of the information you guys have generated concerning this hobby, you have indeed had a dramatic impact on loss reduction, help save the aquarium cash flow by avoiding foolish and unnecessary equipment, between Bob's book, your site, and your willingness to answer questions, I have just turned the three year mark on my 160 which contains of all things a tusk and a blue face (wow, these guys have grown).
<So glad to hear that we've been able to help! Believe me, the pleasure is ours! Scott F. with you today!>
I am slowly nursing back to health my show queen (Bob's book nailed it, it is incredible how intelligent, curious, and not to mention gorgeous these fish are), I have over time changed over 1/2 the water in the tank, used pH buffer to obtain optimum levels and used Maracyn 2 to cure what appears to be a nasty internal infection. She still is not eating, but finally seems to be coming out more often, hopefully she will be eating again in a day or two (has not eaten in a week, ouch!).
<Once she starts feeding, I'll bet you'll see a dramatic improvement in her condition!>
Now down to the question of the evening, I read the archives relating to temps in reefs but did not see a guideline as to how much fluctuation per day is too much. I have two 175 halides (and thank you for guiding me toward halides!) on a 55 (I wanted to maximize the amount of tank space that I could grow SPS), the temp even with the fans shifts from 80 to 82 per day. I did see on your
page that one degree is acceptable, but wondered if 2 degrees is ok, everything is doing great! (well with the exception of the below stated).
<I feel that a two degree fluctuation is reasonably acceptable in a coral grow-out tank. If you are keeping extremely delicate fishes, such as some tangs, which demand high degrees of stability, this would be about the limit. But think about it- in many lagoons where some of these corals may be found, tidal changes can result in dramatic temperature shifts over the span of a few hours. As long as the "highs and lows" fall within acceptable ranges, I wouldn't be overly concerned>
It seems the only thing that I cant keep alive is (strangely enough) Montipora digitata, which is exceedingly strange, I have had tremendous success with Acropora (even wild colonies, I have a nuclear green/yellow Acro from Tonga, which I am fragging, let me know if you want one)
< :)  >
, and capricornis. I did  recently start dosing Iodide, I had always used the formula GARF specifies, but Iodide was not included. I have already noted even greater polyp extension on my acros since I started dosing fractional amounts daily at Anthony's urging.
<Your observations are similar to those of many other reefers- the fractional dosing is important, to establish a "baseline" for your system. Always test when you dose!>
Once again thanks Tom
<Tom- sounds like you've got the whole reef thing almost wired! Keep up the good work- and most of all- keep having fun! Regards, Scott F.>

Temperature vacillation of marine system
Sirs
I have a new set up. 100 Gallon tank. All is going well, with the exception of the water temperature.  
My office is 74f and the water temperature fluctuates from 76f-80f. when the lights go on.  Please can you confirm if this is acceptable. Should I invest n a chiller unit.
Regards Paul Williams
<Hi Paul, A fan or two will perform the cooling/ventilation function you need to maintain a steady temp. while the lights are on. This will also save you during the summer heat depending on where you are, your summertime temps, air conditioning, etc. 80F is just fine if it is steady. Perhaps set the heater at 79-80 and time fans to come on just before lights and off after, or use a thermostat to switch fans.  I would recommend fans first, chillers are spendy and not always needed. If you are in Florida, New Mexico, Texas or Arizona without air conditioning you will want to look at a chiller.  A degree or two isn't too big a deal, but try to keep it to a minimum.  Craig>  

Salinity & Temperature
Dear Bob:
<Connie>
I was at a meeting of SeaBAY last night (in SF area) and learned that the salinity in my LRFO tank should be at .025, also that the temperature for my tropical fish should be 80 degrees.  Do you agree?,
<Mmm, most systems will do best at near seawater conditions. About 1.025 for specific gravity... and 80 F. is about right for many tropicals... but there are arguments for keeping most cooler, some warmer. You can read about these on WetWebMedia.com>
My salinity is now about .022 - over what period of time should I raise it to .025, if this is correct??
<No more than 0.001 per day.>
Thank you Bob.
<Welcome. Bob Fenner>
Connie C.

Thermometers
I have read that it is not a good idea to put anything metal in a saltwater tank.  I have a 110 gallon reef tank.  I am shopping for new thermometers and have come across stainless steel and titanium types that look interesting as I am looking for more precise accuracy.  I was wondering what your thoughts were on these items and if they would release metal ions that would harm the tank inhabitants.  Thanks for your time.   Abby Kengersky
<Titanium? Wow... I would select for a good glass encased thermometer and not be too concerned with absolute accuracy. More important to be precise (get about the same reading each time), that is, to do your best to measure and maintain stability. Bob Fenner>

Chilling Out!
Several Months ago in summer, I purchased an Aquatherm Chiller/Heater from Flying Fish Express thinking it would maintain the chosen temperature of 77 degrees F. by merely setting the thermostat to same and it would switch as necessary between heat and chill automatically. No, you have to manually change it over several times a year depending upon the ambient temperature. Is there such a device made and finally what is your evaluation of the Aquatherm in comparison to other brands?  Thank You for your valued advice and opinions. Stephen Pace.
<I personally have no experience with the Aquatherm brand. You may want to post on the wetwebmedia.com chat forum to get your fellow hobbyists' opinions on the product. I have used the Medusa dual stage temperature controller with good results. plug in your heater and chiller to the unit, and set the desired temperature. The unit energizes either the heater or chiller as needed to maintain the desired temperature. There are other manufacturers making this type of unit, too. Do check our sponsors' web sites for availability and pricing. Good luck! Regards, Scott F>

Warm Enough?
Thank You, Scott. I will lower their temp. Should I keep it around 78?
<I think 78 degrees is perfect!>
If I have a pretty stable system how often should I be checking AM, Nitrites, PH, etc.... It is a 60 gal and we do at least a 5 gal water change weekly, but I usually only test water maybe once a month. Should I be doing this more? Thanks in advance!!! Freckleface
<Well- I'm fairly conservative...I like to do once a week checks, but many successful hobbyists perform checks bi weekly with good results. As I always tell people- don't get crazy about trying to hit an exact nitrate reading, etc. Instead, look for how well your tank is doing- spot trends, note changes in formerly stable parameters. You can learn so much by following these trends! Have fun, and continued success! Regards, Scott!>

Some Like It Hot?
I read in an email you had with Linlee that increased temperature is not good for the fish as it decreases their life span. Is this correct?
<Well, as a general rule, warmer water temps do speed up metabolism, waste production, respiration of animals. In theory, this can increase growth rates and shorten life spans. However, the more immediate concern is the lower oxygen carrying capacity of water at higher temperatures.>
I mean did I understand what you wrote. It sounded like you were saying it speeds up the life cycle of ich and all other animals in the tank... Ideally what temp should they be. I have kept them at 80 thinking it is preventing ich,
but I also don't want to shorten their lives....
<Not sure who wrote that response, so I can only offer my opinions, but I think that you'd be better served in most cases keeping the tank temperature less than 80 degrees. IMO, Ich is prevented mainly by stable water conditions, including temperature, regular maintenance, good diet, and initial quarantine of all new animals. Yes, higher temps do speed up the life cycle of ich, and are a potential assist in ich treatment, but I would not call higher temperatures a "preventative", and would not keep a tank over 80 degrees on a regular basis. Other considerations include even higher potential temperatures during the day, when heat from lights can be problematic, particularly when you're already running a tank at 80 degrees plus. There are two sides to every coin, as the expression goes, so do some research on temperatures in aquaria on the wetwebmedia.com site to get the whole picture. Thanks for stopping by! Keep your cool! (sorry- couldn't resist that!)  Scott F.>

Tank Temp
I recently upgraded my lighting on a 75 gal reef tank( SPS, Tangs) from 260 to 440 watts. I live in a four season climate area. Going into winter I am trying to maintain a steady temp. but having some difficulty. My tank fluctuates from 80.8 to 79.7 from day to night. Is that too much fluctuation?
<No. It's actually better than the nominal accuracy of most aquarium heaters, which is +/- 1F.  Less than 1 degree isn't an issue.>
The lighting unit itself has 4" fan in it that runs while the light is on. I also have a clip fan blow directly into the sump that also runs when the light is on.
<You may need more or bigger fans in summer.  No worries my friend!  Craig>

You give me fever... Natural and captive reef temp.s
Thanks for this. What you say below all makes good sense, and in line with my studies. But how then do we reconcile a chiller creating an artificial temperature cycle two or three times a day as it's thermostat cuts the unit in, the unit drops the temperature, unit stops, temperature rises, thermostat cuts the unit in...
<Really the unit should not cycle that dramatically.>
Particularly given that the variance against time is the issue, rather than the actual value (given that it is within acceptable range). Wouldn't I be best to let the tank ride the seasons variance?
<This may have some added benefit, particularly if you are experimenting with bringing about a spawning event, but it would be experimental.>
This would see an annual change from 26 to 32 in summer but with good stability over days/weeks.
<Correct>
I have bought/installed a chiller based on advice from everyone (I live in Sydney with Metal Halides), so maybe I am dreaming to think it can be kept to 32 maximum. I haven't had a summer yet with this setup so I don't know. I am skeptical and selective about taking advice on anything in this area (marine aquariums) but there seems to be a fairly consistent opinion here. Am I best to have the temperature range on the chiller set higher (say from 27 to 29) so it cycles less?
<That still seems like a large range, 80-84*F.>
What is the lesser of these two evils, variance or absolute?
<Stability is preferable.>
Any suggestions for further study (I prefer a correlation with field results  if possible).
<You can always check out the National Oceanographic and Atmospheric Administration website, http://www.noaa.gov. They have data on coral reef temperatures.>
Many thanks for this quite unique (conservation) resource! Michael Peters
<You are welcome. -Steven Pro>

Reef Temperature
Good evening/morning crew,
I am coming into summer here with a 6 month old reef tank which seems to be doing very well (thank in part to some of your good startup advice, thank you :).
<You are quite welcome.>
I am curious to have some advice on the impact of temperature and variance of this parameter. I am running a couple of Metal Halides so they lift the tank temperature through the day, dropping again over the dark hours. My water temperature through winter has hovered
around the 26 to 28 degree mark. Now with summer arriving, the temperature has moved up to the 27 to 29/30 degree mark. I have noticed that my LPS corals seem to more fully extend in these higher temperatures and also my clam. Is this a coincidence or is there likely some correlation?
<Your temperature is now varying daily from 80.5 to 86*F. That is too big of a swing and too high of a peak for my comfort. Temperature swings are one of the biggest triggers for Cryptocaryon outbreaks. There is probably no correlation with your corals. Their metabolism will be higher at higher temperatures, but enlarged tissue is a deceiving thing to watch for the health of LPS corals. You must monitor calcification for an actual determination if the coral is doing well.>
Does this mean they are happier/healthier?
<Not necessarily.>
I see a lot of writing (all?) saying that temperature must