I have a Topfin 300 watt heater in my 75 gallon and I'm looking to replace it. I'm currently dealing with either ick or velvet in my tank and am trying to get my temp to at least 86 degrees. Since I've been watching my temp like a hawk I'm realizing what a bad heater I have. The temp flucuates way too much and can not keep the temp above 80 at night. (Our house is 68 at night and 70 during the day). I did not want to buy a second cheap heater from my local pet store but would rather spend them money on a well built and reliable one. Any suggestions?