I have a 150 FO tank with a trickle filter. I open the top to the trickle filter and put a fan on it and I open the lids on the fish tank. I also leave 2 of the 4 lights on most of the time. My tank was up around 82 to 84 before I did what I do now. It's worked really good. The other side note that is pretty important is that you have to have the air conditioning on in the house!