Filtration Question

I currently have a 45 gallon aquarium with a VERY large tinfoil barb..some
angels...tetras....gouramis...etc.
I have 2 Aqua Clear 200 (?) filters running. I clean my tank at least every 2
weeks and do water changes/add as needed.
My water has never been completely crystal clear. I test it weekly and
everything is fine. I think my problem is I have fish that provdie a large
waste load. I want to add more filtration to my tank and get the water crystal
clear again. Any suggestions on what filter system I should buy?? I want
something that will keep my tank clean and my water clarity clear.
Cyndie