Pump sizing question

[P.Kelly]

I have a 92 gallon AGA corner, with a "corner" overflow rated at 400gph.

1. Has anyone validated that 400 gph is the actual flow (is it a little higher or lower?)
2. I have a mag 9.5, which flows way too much water at about 4 feet for this overflow. I'm currently running a mag 3 on it, which is not enough, the mag 5 is still undersized and the 7 is oversized. Can I install a ball valve and restrict the the flow?
3. If not, any recommendations on a good pump that will get me real close to 400gph at 4 feet?

 

[Grins]

My pump is an Eheim 1260 rated at 635gph and yes you can adjust it with a valve.

 

[P.Kelly]

And are you running a tank with a 400gph overflow?

I know that you "can" restrict the flow, so I should have asked what negative effects can I expect from actually doing so? More wear on the pump, etc?

 

[deklin]

A ball valve on the output of a mag pump would work fine.

Although if you don't like paying for unused pump power, you could sell your 9.5 and replace with an Eheim 1260 like grins mentioned, should be about right for a 4ft head and will run quieter and cooler than the mag.

 

[Randall_James]

you can restrict the mag 7 or just "T" the return line and put a valve in the new line (return some water to sump)

Just restricting the pump will not hurt it at all.

 

[here goes!]

Be careful if you use a ball valve, they are meant to be on/off and not to restrict flow. The theory is that pieces can break off of the ball and cause it not to seal properly or cause damage down the line. Gate and needle valves are better suited. Personally I don't know of anyone who has had this be a problem, just a heads up.

 

[P.Kelly]

here goes! - thanks for the advice on the gate valve instead of a ball valve.

 

[Randall_James]

I do not think I would spend the extra on the gate valve ($15+ Vs $3-5) Plastic PVC ball valves have nothing inside to break. They are a simple valve and the biggest problem they face is locking up after long long periods of use without opening or closing. A ball valve only has 1 moving part

Gate valve is easier to adjust but for what you are doing, I think a ball valve will be easy enough to adjust