If you want to get really fancy you could do a RFUGF. It is a classic underground filter, only reversed flow. Instead of pulling crud down to the gravel, water flows up through it, pushing any solids into the water column. Then you can add a HOB or canister to filter out the solids from the water. This is very eficcient and will minimize the ammount of gravel vacuming you will have to do(notice I didnt say it will eliminate gravel vacs). With less waste build up in the gravel, you will have less of a chance of nitrates building up down there.
