Return Pump Question

[molotov]

Hey daplatapus, long time reader first time replyer

Your bang on with one of your comments. It turns out I didn't have enough water in my sump. Thank you so much. I don't want to go to bed and have my system in limbo.

One more question, i have gravity feeding my ATO on a float valve. Would I place that float valve in the chamber where my return pump gets its water from? Or the chamber just before the bubble trap? Thanks again sir.