My question is about the pump used to push the water up from the sump. the pump im looking at is used, rebuilt and near here I live so ild like to buy it, its 850 gph. By cliffs article on sumps I need about 725 gph, I think. Tell me what you think. Three feet of head(distance between sump and tank) at least two 90's two 45's, one check valve, ten gallon sump, 29 gallon tank. I'm scared to put too much power on this as it will cycle water through the sump faster, and dont know much if it will be too much current. Not sure what the head rating on the pump already is.