Ive been thinking about setting up my 10 gal. for smaller fish - Guppies, Zebra Danios, and maybe even an African Dwarf Frog and Beta. Firstly, would these fish be good together? Secondly, I told the guy at my LFS that I was running short on electrical outlets and only had two open ones with three needed items - light, heater and filter. He said that all of these fish (and frog) do fine in cold water and that I wouldnt even need a heater for that tank. Is he right?