I filter going into tank with a charcoal filter and coming out of the tank immediately after the pump. I filter with charcoal going in to remove taste and chlorine, I have heard chlorine leads to tank failure in an aluminum
tank. I filter after the pump cause I have enough lime or hard water deposits that come out of my tank that it will over time clog the aerator on the sink etc. if I don't filter.
I have a seagull filter for drinking water
, Seagull came with the boat, I doubt I would have bought it, I think them over priced.