Advice on return pump for sump

[jgr]

I'm in the process of converting my 75 gallon freshwater tank to a reef tank and am in need of a pump recommendation for my 40 gallon sump. I'm using the CPR CS100 overflow (800 GPH) and from reading past topics, I know that my pump should not return more than 800 GPH back to the tank. The tank is exactly 4 feet above the bottom of the sump.

Will the Mag Drive 9.5 (800 GPH at 4') be okay? I.e., will it end up returning more water than the overflow delivers to the sump? I had hoped to find a pump that was rated at 750 GPH at 4', but such a pump does not appear to exist.

Thanks in advance for the help.

 

[mrcrazypants05]

Couldn't you install a ball valve on it?

 

[jgr]

I hate to ask a stupid question, but what exactly is a ball valve?

 

[mrcrazypants05]

"A ball valve (like the butterfly valve, one of a family of valves called quarter turn valves) is a valve that opens by turning a handle attached to a ball inside the valve. The ball has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends of the valve, and flow is blocked. The handle position lets you "see" the valve's position. " googled...

I don't know much about it, but I think the python gravel vac's use a ball valve to regulate flow on them... so if you have one... I believe thats what it is.

 

[Macrosill]

The Mag 9.5 should work well with a ball valve(fancy term for a plastic 1/4 turn shut off valve) to control the flow. Here is a pic: http://www.watertanks.com/category/137/

 

[jaiden]

Often, people put in a T on the return pipe which feeds back into the sump. that way your pump can run full blast, but you can adjust exactly how much goes up to the tank. One thing that concerns me about overflows (and I don't have a sump yet) is that the overflow is rated for so many GPH, but if a snail gets in it, that will go down drastically.

 

[tecwzrd]

Most overflows have a screen or sponge to keep fish/inverts out. A T (one on each end of tank) is a good idea to keep your water moving other than just one direction.