Skimmer vs Pump Size

[James5]

Relative newbie to the pond world and I plan on installing a skimmer to my new pond design.

What relationship is there between the skimmer you use and the pump size you use? Seems to me that if your pump is too big it could suck the water out of the skimmer faster than it comes in. Or does that action just pull more water into the skimmer? And also, is there an issue if, say from evaporation, the water level in the pond drops too low and pump runs dry and burns out?

Tahnx,
James

 

[Waterbug]

The door on skimmers open more as water level falls in the compartment either because of evaporation or the pump pulling. So the height of the door determines the water level range the skimmer can support. Manufacturers define the mounting height of the skimmer for the desired water level. Normally about 1/3 down from the top of the door (weir).

Manufacturers rate their skimmers by GPH so you know pump size. Exceed that and the skimmer is likely to suck air. Also, as the skimmer basket (assuming no sieve) clogs a pump at the high end of the spec will draw less water. A lower GPH pump would be able to run at max GPH with some clogging.

 

[James5]

That makes sense :surprised:

Thanks again, Waterbug!