I'm getting ready to start up my 125-gallon tank. I will be using a sump for this tank. The tank was originally used as a reef tank and was set up with hard (PVC) plumbing. So, my question is, I have a manifold plumbed above the sump and was wondering if I could use the manifold to replace the use of a (250 gph pump) which is recommended by Aqua-Medic for the "Aqua-Medic 1000 Co2 Reactor".