Replacing a liner in a 16x32' inground pool

[PoolDoc]

Raising the bottom will decrease the volume even more......easier to solar heat the pool

Not as much as you think -- most of the heat loss in an AG pool is from the surface, and 2nd most is from the top 12" the pool sides.

[DIYLINER]

Actually it will make quite a difference, since we have a stream on the property & groundwater flow
The groundwater flow constantly cools the bottom of the pool
The 1st year we lived here we hardly used the pool as it was too cold
With solar heat the 2nd year temps were in the 80's
Insulating the bottom against the ground water flow will make a big difference, just wish the whole pool had been insulated when installed

[PoolDoc]

Insulating a pool can make a difference, but it's still true that your major loss is via the surface.

[DIYLINER]

I had a cover the 1st year we moved in, I did not have solar heat
In my case the major loss of heat is thru the ground