Quote Originally Posted by dep78737
When there is a major restriction in suction, the pump might be cavitating, causing the water to "boil" in the basket. You might also be creating a suction leak at the pump lid when the restriction happens. Are you allowing some suction through the skimmer or drain while vacuuming/cleaning so it's not all concentrated on the one device?

I feel we are getting somewhere here...
I have only one skimmer and the drain at the bottom of pool is not working. So when I plug the vacuum in the hole at the bottom of the skimmer... the only water going in is from the vacuum. Any suggestion on how to let some suction through the skimmer?