I rinsed it a second time in tank water and that seemed to do the trick. It's not going over the bypass anymore. thanks to all who replied=) I've read that the carbon contained in the filter pad isn't usually very effective after a couple weeks. Does this matter? I read an article here by Goldlenny that suggested removing the carbon from the pad to improve the flow rate. That makes sense if the carbon is no longer useful. Does anyone else do that? There is an initial chamber of water at the beginning of the filter, before the filter media, can I add some carbon to that chamber? Or is the carbon important at all and can I do without it?