betta velvet illness snails

Hi all! First post, so a quick intro. My name is Shauna, and I adopted 2 betta fish, Phinneas (blue crowntail) and Pepe (red & white Dumbo) in March 2016. They both live in a 5gal filtered tanks with a heater & a fan (I live in AZ) that are controlled by a thermostat so the tanks stay, in...