Proper Wattage for 90 gallon heater


Reefing newb
Hi all,

I have a 90 gallon tank that I'm setting up to be a reef tank. I keep my house at 75 degrees F all summer and winter long (im in Florida) and it's central air so a pretty stable environment. I was thinking about purchasing 2 250 W heaters for the tank. Is this appropriate or too much?


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sounds good to me, a 250W would be perfect in a sump but having two gives you a fail safe if one were to go bad

are you going to use a controller? I highly suggest getting one if you are going to run two heaters
One thing I consider in my selection of a heater was the fact that I live in a very warm climate most of the year. I live in Arkansas where 110 F days are not uncommon so the temp in my house year round stays around 77-80. With that said, I have a cooling problem more often and a heating problem. I have a 120 gallon cube with a 30 gallon sump and I am running 300Watts heater and it barely ever turns on's because I keep my house so warm. In other words, I believe factors other than water volume and wattage should be considered. I do agree that two is a good idea, and maybe a third in the closest:)
Thanks for the info. I was worried that I may have to get a chiller. I'll be using T5s for lighting and I'm sure they'll add some extra heat to the system as well.

I will eventually get a controller but probably not till later down the road. I was looking at the ReefKeeper Elite. Any other suggestions for controllers?
I have the reefkeeper lite with 2 pc4s (thanks again Marinne) and its a perfect controller for my 125 gallon. I have exactly 8 plugs on my tank. I run one 200w heater but have the alarms set close to the set temp sp if theres a problem I have a chance to grab the heater from my SW mix barrel. The room where its located runs a consistent 70-72*, and I have an 8 bulb t5ho light and submerged mag 9.5 return pump.