[Tangster]

I'm just offering what I know from experience take what I offer for what you feel its worth. Are you drilling this tank for bulkheads for the pump you want to dedicate to the circulation of the tank ? Also who ever told you that a Mag 1800 would run that system has not a idea about how much water a 1 inch pipe can drain .. Is the tank reef ready ? As for manifolding these pumps together can't do it if they share any common connection then its going to mess you up.. You will need the one 9.5 to simple lift water from sump to tank this will push about 500 GPH through the sump and allow the skimmer to di its job the dedicated circulation pump has to be fed direct from the tank then you can manifold them to the 2 4 or 6 bulkheads located around the tank to move water currents . I have a few Gen X pumps now and not a good choice you want a Little giant high Volume low pressure pump to circulate not a high pressure high head pump. like a little giant 4MDQX-SC to circulate the water around in this tank..