bought filter at home depot, its bad ass and perfect. ya 3/4 in return hose with only 1 1/4 pvc connecting the system. pump is a active agua thinking 650 ish but not sure exactly at the moment. plants oh how I miss them already. we getting ready to move so going to have things shut down until we find a place.. hoping less than a month, ugh. its crazy every since we started growing we haven't stopped its been like 3 years. starting to have withdraws from the lovely ladies.. we had to finish building the uc system so could test for leaks on the concrete floor. not really tryin to tear the carpet out of the next room I use... thx guys.