Hello Everyone! I have had a busy weekend setting up my 125g. I got it all filled up and let my sand settle, then I started my filter it is a Tom Aquarium RP3 Plus. I don't think anyone else uses one on here but if anyone does or if anyone can help me the return pump is rated at 700gph. When I put my hand in front of the return line the flow feels pretty weak to me. I am just wondering if I am paranoid I don't have enough flow or what but I think 700gph out of a 3/4" tube should be about 11.5 gallons a minute and it doesn't seem like it. Can someone give me an idea how much water flow I should have is there a way to check it beside just sticking my hand in front of it and feeling?? Thanks so much. This site has answered all my questions I have had and then some. Very informative post and people!