Pinholes?

[derpmeister]

Is this the plastic bottle baffle you tried?

http://www.petfish.net/kb/entry/347/

I use this on mine, and he can't really swim in it because if you do it right it leaves very little space. Works great.

If this is the one you use, I suggest using the sponge baffle idea. It'll reduce the flow and also give more space for good bacteria to grow on.

[XSprinkleFaceX]

I did the bottle baffle idea they showed on this forum but I guess since my filter isn't the same it didn't work properly. I now have the sponge baffle in and its amazing! Plus, just like you said, it's a good place for the good bacteria to grow on :)