Hello,

I just bought a house that has a gunite pool with a single main drain. The pool is probably 40 years old.

I haven't been able to locate valves that deal with the main drain nor the skimmer.

I noticed that dirt around the main drain doesn't get sucked in and also confirmed that the main drain doesn't seem to be working.

The skimmer works just fine.

A pool cleaning guy suggested that I test it by putting in a tennis ball to cover the skimmer hole to see if the main drain would then start to suck.

My questions:

1. Is that safe to do?

2. Is it normal that old pools don't have any valves to control the water flow?

Thank you.