I know that is a challenge for nano tanks to keep their cool in the hot summer months. My 30 gallon breeder looks great one day and slowly going into siesta time the next. My house is running a.c. and I have the cover open on the top with a large fan constantly blowing trying to keep it cool down. I'll post pics later. My rainbow bubble tip nem split and now it wondering around and I think it's from the high heat.