Sand base problem

[dante1]

Hello everyone,

I recently purchased a new liner for my inground pool. The installers came by yesterday to install the liner and upon removal of the old liner...they notice that my sand bottom in the deep end was completely washed out. Basically, below the steel walls where the sand bottom starts, it seemed like there was a landslide. The installer told me that I need to put a cement base as the sand base was not repairable. I spoke to someone and they told me that 4" of sand MUST be removed in order to have a solid base, otherwise it won't last. Is this true? My installer told me that he would put 1" of cement in the shallow end and 3" in the deep end. Is that acceptable? Also, I noticed about a foot of water today in the deep end even though they removed the liner yesterday. Is that normal?

Any advise would be GREATLY appreciated.

Thanks,

Dante1