I recently upsized my sump and now have an 11 gallon refugium for my RSR 250 system. I have Chaeto in there and need some type of powerhead in there as the flow for dosing, although I have a Vario 2 at full speed, is not quite enough to prevent precipitation of 3A & B with the way the water enters the sump. Does anyone has suggestions on a pump, and a way to prevent it from getting clogged with bits of Chaeto? Don't really want to buy something new. I have a few here, a Hydor nano, MJ1200, some really small cheap thing, and a Cobalt Aquatics EXT In-Line Pump.