okay I am used to having a sump and my ato feeding into the sump. I would like to add a ato to the 130 but I worry about it back siphoning . should I be concerned with that? was looking at CORALVUE Smart ATO-Automatic top Off System anyone using this ? actually as I write this I am thinking as long as feed tube is above water line back siphoning should not be a option, so what a you using on your 130 tank ?