I haven't done a water change since May 30th. Every 3 weeks I take the bottom apart and also clean the canister filter inspect parts and clean. It can take me about 4 hours. I only add one gallon of saltwater because I lose a little saltwater. Every Sunday I just clean all the filters.: Surface filters, filter socks, DC pump filter, skimmer cup. But when it's done I get pretty good results. Let's get it done..🙂