Yeh, I agree with Becca. I use three of these in my tank which is about twice the size of yours. With all of them, I removed the filters to improve air flow. Two are completely inside the tank recirculating the air and the third is on an end wall pulling air through the tank. I also have misting nozzles assuring humidity stays high. I think you are fine with one fan if you take off the decorative mesh piece from the front. If you need a second one, you can always add it. The 4" model is much louder than two of the 3" fans would be.
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