I completely forget where or if I heard this but I think I might have invented a biological filter/ nitrate reactor( I'm really not sure)/ refugium. So you have a big piece of PVC
tubing( as big as you can fit. I could do a 3 ft tube 3 in diameter) and you put a light at the top connected to and end cap. At the bottom there is also an endcap. You get a piece of silicone tubing to use as a syphon. Drill the side of the top end cap so the tubing can fit in. Cut a square in the top of the PVC
tube so you can fit a 45 degree PVC
fitting on it. Glue the fitting in the rectangle you made. Get a pump for the out take and fill the tubing with live rock rubble and macro algae. The pump pushes the water out through the fitting and in through the top cap. It would take nitrates out of the tank and all that good stuff. If you know who said this already or If I just dreamt it tell me. I do not mean to plagerize. Thanks!