The fluval line is good but just has a crappy design. It's like they tryed way to hard on it. Either way I made a little modification to my 304 that makes it a pretty **** good filter. Check this out all you fluvaler's
Awile back i made the mistake of buying a "trash can". I got aggravated with the bin setup it had going on inside cause it used up alot of valuable media space.
So what I did is took all three bins out and the foam holder thing and the bin top, so I had pretty much a empty bucket.
I then took the bins and stored them away in case my project didn't work.
Then i took the foam holder and traced it on some 1/16in plastic. then I cut out the peice and cut a gap in the bottom so water can pass under it.I alos drilled acouple of holes for added curculation. It looked like this.
I put this insert on the foam filter side of the bucket and slide the foam holder back in to place.
It looked like this
In the end I put "one" of the bins back in the filter on the bottom with the biomedia that came with it. Then I filled the rest of the media side with bioballs and put the bin top thing back on. But, you could fill it with what ever you want.
The filter actually run quieter and in the end much better. I hope this helps all you trash caners.
PS: I have been runnig it for months now and nothing has gone faulty in the moter. But, if it does fuval will never know you tampered with it cause you didn't modify the filter it self in anyway. >8)