help! water too warm 86 degrees


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Help! I just set up my first marine tank, 65 gallon AGA overflow, reef sump rated at 75 gallons(11inches wide by 20inches long, 14 inches high). Lighting: 36 inch Coralife Lunar Aqualight with 196 watt 10k and 196 watt actinic.

My local fish store recommended that I put all my equipment inside the sump. The items I have: Super Skimmer 125, Mag 7 for the return, CAP 400 pump for the UV 9 watt turbo, and a stealth heater. It was a puzzle but I was able to get it all in the sump. Right now I'm just running salt water, checking for leaks and adjusted water chemistry. With the lights off the temperature is at 84 degrees, with the lights on it is 86 degrees!

My question to anyone: are there too many items in the sump which would cause the temperature to rise to 86 degrees? If not, what else could be causing the high temperature?

Secondly, if I leave the equipment in the sump will it cause future maintenance problems as far as difficulty in cleaning the sump and collection of detrius.

Your advice would be very much appreciated.
I don't have my aquarium setup yet, but from what I have been reading the pumps are probably causing your problems and maybe the lights. I am going to use external pumps on my system which will help reduce the heat of the water. Also, you could install some fans in your canopy to reduce the heat of the lights. But, it sounds like you will probably need a chiller.
i would try 2 things befor i went out and bought a $400 chiller. Double check the heater. Theres nothing in the tank so unplug the heater and see if the problem gows away and 2nt install a fan so it is blowing accros the surface this should help and if there is a canopy on top make sure there is plenty ov ventlation
house is at 76 I unplugged the heater, UV/pump , (mag and skimmer still running ) lights off last night ,this morning was 84 (open top no cover)
very strange.

i have a 65g AGA tank, just like yours, i run 3x96w lamps over it and the tank gets up to about 80-81F during the hottest part of the day.

All my equipment is in my sump as well, where is your thermometer in the tank?
Using a Mag7 in-tank could add several degrees but try not to get in too big a hurry, water takes a long time to heat or cool. Turning off the lamps should have dropped the temps by at least 4 degrees. Blowing a fan across the top should also drop at least 2-3 degrees while increasing the need for fresh make-up water. Your lighting is not as hot as metal halides so that's O.K. but the 3 skimmer, return, & U.V. pumps are most likely the source. With no life in the tank take the skimmer out too and see if just the one Mag7 is the culprit. Worst case would be to drain the sump, drill holes for bulkheads and install the return outside the sump. Acrylic is easy to modify if you chose. Adding a chiller is a no brainer for a solution but in a central A.C. room really should not be necessary.
Cut back to only one motor and run for at least 48 hrs before adding another to try and zero in on the worst offenders.
William Fisher
Add a fan blowing across the sump and let us know what the temp changes too. I'm pretty sure that will fix your problem- u'd be surprised what a small fan would do.

I cool my house to 72-73 just for my fish tank :)

Leaving the equipment in the sump is not a problem. You may wanna blow a powerhead around in there the same way you would blow your rocks to put the detritus in your water column so it can be filtered out of the system.
Update ..thank you all for the info the temp is at 80F to 81F with two fans during the middle of the day with lights on , It seems to be stable also I did discovered a rare problem on my mag 7 pump , I ran a hose line out side the sump to see if I could drop the temp before I drilled the sump,and turn it on water was leaking severly at the seal where the 4 screws held the casing ,opened it up to check it out and found there was no o-ring installed. based on the Mfg specs online ,took it back to the LFS (small advantage of buying local instead of online ) and they exchanged it and they said it was very rare, so I wonder if the pump was not being at full capacity had anything to do with temp , now I have everything in the sump sgain and and ready to move forward . once again thanks for the help.:)
i just recently had this problem with my new 75 gallon and it was runnign 80 with the lights off and would rise 5 degrees when i put the coralife aqualight pro hqi. I have alot of pumps and powerheads in the aquarium and what we ended up doing was putting the sump in the other room by cutting a couple small holes in the wall for pipes and added a chiller. Befor ewe did this we unpluged one thing at a time and wached the temperature too see what changed the temp the most. It is possible that you have a bad pump.
keep in mind that a UV sterilizer adds a TON of heat as well.
What are your plans for the biotope? Is a UV going to even be a necessity?
I agree with Tony. Remove the UV and it's associated pump for now. That Mag 7 will add a good bit of heat, too. You may find it necessary to go to a Mag 5 to solve your heat problems.

And as gwen mentioned, using a small fan to induce evaporation is extremely effective - for every gallon evaporated, you remove 12,000 btu from the system.
I agree, We usually don't run UV on our reeftanks round here. (Augusta) If you are planning a fish only then it would be beneficial.