I'm getting my plans together for my next freshwater tank. I was thinking of incorporating the old school undergravel filters for pumping filtered water back INTO the tank. Water would drain out of the tank via an overflow, filter in the stand and get pumped back in the tank from below the gravel bed. This would hopefully create a slight but steady updraft which might keep some of the crap and excess food from settling in. Some of this waste would end up in the filter as the result and would cut down on the gravel vacuuming required. Any thoughts?