Uhg.. I wish I had looked at this sooner. Your going to end up hating that sump. work ok while clean, but as soon as it gets a bit dirty, the flow going to the various compartments gets all whacked. The refugium part is pretty much worthless as the chaeto ends up blocking the flow in that chamber and the water just finds it's way through other channels. I would just put a Brightwell export brick in the refugium and call it good. Buy extra sponges for the slots between the chambers. these get plugged up pretty quick as well and you will want to be able to swap them out. Depending on your ATO, the pump chamber gets a lot of bio film. the IR sensor type ATO ends up having problems. As soon as I can afford it, I will be removing my Eshopps. I am dreading trying to do this on a fully established tank.