Too much suction !!

[KurtV]

Thanks everyone for your input.
Answers to questions: I really dont know if we have a main drain or not. Where might it be located?
In the bottom of the pool.

When we partially drained the pool -- just used a small pump.
Only have one skimmer
I have been told the pool is gunnite.

Boughr a new head at walmarts today--going to try that tomorrow
Again thanks
Karen

Is there a valve or valves on the pipes the go into the suction side of the pump (the side that has the pump strainer on it)?