WTB: External Water Pump
 

Like in the title an external water pump. need something around 400-500 gallons per hour.

you best off to go with a Reeflo Snapper.

as you allow less flow to go through, it uses less power. PLus its very quiet....

the are around 200$. New

Is 400-500gph @ 0' headpressure?

the snapper is 2700 GPH @ 0 head pressure.

but if you put a ball valve on the output of the pump, and throttle it back to about 1/4. that would be around 600GPH @ 5ft of head.

Thanks for the response. If i m able to add a valve to it to decrease the flow it should be fine. what does "600GPH @ 5ft of head." mean?

"Head pressure" refers to the distance the pump has to push the water up to where it returns into your tank. The greater the distance the pump has to lift the water, the more pressure it will loose. Try searching out head pressure loss calculators on RC or maybe someone here can post a link.

RC Head Loss Calculator

When you calculate for your loss you also take in account your horizontal and fitting loss, this give like a total head loss. From there you can figure your flow from the pump charts (flow vs head). The RC calculator does this automatically but a concept helpful to understand.