Tank temp advice needed

[ptcpilot]

I am slowly setting up a mixed reef in my 75G. I just installed an Outer Orbit (2 150W MH/4 T-5 Actinics) lighting system on legs and 2 Koralia 2 powerheads. I am also running a MAG 7 return pump and a skimmer in my approx. 10G sump. To keep things cool, I am running a clip-on fan into the sump and a full-sized fan aimed toward the top of the aquarium to dissipate heat and keep the temp as constant as possible. I run the T-5's for 8 hrs daily and the MH for 5 of the 8 (MH 8am - 1pm). My tank normally runs from 78 - 80 degrees but on the hottest days I am up around 83 and we haven't even hit 90 degrees outside yet. Is there a normal/abnormal range of temperature change during a 24 hr period that is acceptable or do I need to look at getting a chiller? If I need a chiller...recommendations?

Thanks

 

[ptcpilot]

I'm looking at a 3-4 degree swing in 24 hrs

 

[tokejr]

The one time my tank got too hot, I put a frozen polar pak (inside a sealable plastic bag) into the sump to slowly bring down the temp. Then I adjusted the heater to keep the temps reasonable.

This tank (my 30 gallon) is upstairs in the loft and the air temps there get hotter than the rest of the house - heat rises - but I've never had it over 80 again. I keep the ceiling fan on and the air at about 75,

 

[theplatypus]

The PCI 1/10th hp should be more than enough for a 75.

 

[sj miller guy]

I have the same kit on my 90 gallon. Ever since adding that I also added two cooling fans into the canopy both blowing in cool air. These run from the time the light kit turns on, until it turns off. My actinics run for about 12 hours and my halides for about 7.

One of the things I did to help was to change my light cycle. My actinics come on about 10:00 and run until 10:30 and my halides come on at about 11:30 until about 6:30. In the summer, i also cut my stealth heater down so low that it basically runs very little if any. I keep my house at 77 or below with the ac on. The highest my tank usually creeps is about 79-80 which is still a little high for me, but I'm happy to hit that without a chiller.

Try a few tricks like that before you have to resort to a chiller. It may have a lot to do with the setup of your lighting and system as well as how hot or cold you tend to keep your house.