Ok here it goes, I have an in ground gunite pool here in south Texas. Its about 6 years old has 2 Skiimmers and 2 main drains and auto fill. First off the water level is normal, and I run all 4 pump intakes IE skimmers and Drains open. Well this morning my wife comes in and says something is wrong with the pool... Great I think, this was supposed to be my lazy Sunday! Sure enough it was sucking air big time into the pump basket. To the point where the pump was losing prime. So here is what I figured out.
With the skimmer basket closest to the pump turned off no air. If it turn it on just a little it sucks water so fast from the skimmer basket it starts pulling in air. Thats with all 3 other intakes open.
Ususally when I isolate just one skimmer, like for cleaning the bottom, that one isolated skimmer sucks so hard it almost begins to suck air. When I isolate the far from the pump skimmer and suck just from that one far skimmer It acts like it's clogged partially. It will feed the pump but not with I would think to be the normal gusto! It provides enough water to fill the pump basket but does not even get a vortex turning in the skimmer.
My hypothesis is maybe the far skimmer is partially clogged and when given the chance the closest skimmer to the pump does all the work(path of least resistance). Anyone know whats going on??
Oh, the far skimmer that I think may have a partial clog usually catches about 90% of the skimmed debris from the pool. Its always the dirtiest by far...........