I have a 29 gal. The current filter really only works when it feels like it. There is a section I can cut out on the other side of the hood because it has some "perforated" squares that I could easily cut out with a boxknife. If I cut out all of the squares, the filter I got with the tank will fit. Should I do this and put the other filter on or leave it alone?

Why/What's going on with the filter that you're currently using? What size/type is it? What size type is the other one? If it's not working up to par,it definately wouldn't hurt to add another filter to help it.But if it's really acting up,you may want to just look into getting a better one. I recently changed out a couple of my 30 gal. tanks and put on Penguin 350 filter's and have been very happy with the job that they've been doing.

The old on eis an AquaClear with a Bio-wheel. The current one is actually only a couple months old. It's a AquaTech. They are basically the same thing only one has a Bio-Wheel. I tried to cut another hole into the hood, but it was so old and brittle that it almost broke the entire back off. So I can't so that.