So I am planning on setting up a 39 gallon hexagon seahorse only(maybe some pipefish down the road) tank. It will be going in my bedroom which is on the 2nd floor in my apartment, my 1st question is, do I need a chiller? In the summer time I have the a/c on constantly and I am assuming(that being the keyword) that the temp in the tank wo't go above 75 deg. F. Is that too high? Also, how many seahorses(& I know it somewhat depends on the species I go with) will I be able to keep in an aquarium that size? Any help would be appreciated.