I just use a standard syphon. I take out 20% of water every timeand my tanks fine...
What you need to do is really stir up the substrate when you do a water change... It'll suck up all the muck from the bottom. If you have a planted stank and can't do that... just get really close to the bottom and wave it around. If you have plants you also want to syphon inside of the really busy ones - you'll be suprised at the amount of muck you'll get out of those!