Submersible pumps

[70NKY]

Hi,

I currently have a 1050l/hr pump running in a sump setup, into a 250l, 4ft tank. My question is, on the box it said that at 1m, the flow rate was 170l/hr. Now the outlet for the return hose would be about 1m above the pump. Does that mean that this 1050l/hr pump is actually only pumping 170l/hr into the tank?? That doesn't really seem right, there seems to be a fair bit of water draining into the sump, my guess is it's more than 170l/hr.

Mick

[Hellboy]

Hope this helps as the 1m is measured from the waterlevel in your sump to the utmost vertical point of the outlet hose. Some contributing facts that will reduce flow rate is elbows and hose diameter and any other restrictions along the way. Most pumps r slightly under measured due to restriction factors and the concern of the manufacturer getting lots of returns due tio the pump not making there ratings. SO u will find that you r getting more than 170l/h exspecially if it optimumal.

[70NKY]

So perhaps if I filled the sump up a bit more that would help to increase the flow? Of course allowing for room should the pump fail...

[Hellboy]

Yes that would help with flow rate. Turn your pump off to let the tank drain into sump fill sump to just below full and turn pump back on. Mark the level of sump after its been on for awhile and that is the level you sump should sit at provided none of the returns become blocked and leave more water in the tank. Otherwise if the pump fails you will have an over flowing sump. Should help you with water changes to know the level your sump should be at without blocked drains.