Guys I WANT TO THINK EVERYONE FOR THE TIME AND HELP FISRToF ALL. I wrote in capital to make clear how to appreciate I'm. But here is the situation. I have no chiller, one tank 50 gallons runs with a cascade penn plex filter for 150-gallon filtration only no sump, no skimmer. Water is perfect condition and 8 small fishes. That was all recommended by Lovely Pets, now the new tank 120 gallons gets the water up to 80dg and has 2 same filter pennplex150 gallons each, only life rocks inside, live sand and cycling before fishes, tomorrow a guy from Petco is coming to install a brand new sump that I bought from Drs Smith for $400 PROFLEX SUMP MODEL #4, and he will install in a couple of weeks the Nyos skimmer 160 $500 ....So Im'affraid after all this equipment the water will even get hotter. So that's why I'm asking if I should use the chiller and if the which model, 1/10hp , 1/4hp? Please help me guys, thanks again