We installed a 21 X 43 X 54" AG Pool 10 years ago. I was never really happy with the job our installers did even though it was a large crew, it was the first time any of them had even heard of an AG pool this size. The sand bottom quickly became full of bumps and knots and there were several wrinkles left especially in the walls. After about 7 years I became weary of the constant cleaning with the bumpy bottom and also found that our filter system was way undersized. So I decided to upgrade the pump and filter and change out the liner and add a gorilla mat. The installer that was recommended to us tried to do it by himself on a very cool day and the new liner is bumpier with more wrinkles than the old. Late last summer, the liner showed signs of leaking and this Spring was confirmed by wet ground surrounding and a pool leak guy placing several patches around a ring made by my constant brushing which rubbed the liner thin. So after 2.5 years, we are having to replace the liner again. First of all, ALL liners seem to be out of stock, so when I can finally get our size, I will have a pool company install the new liner after pouring a PoolCrete (vermiculite) base to make sure we have a smooth bottom. I am also considering a single or double floor drain and if necessary, a 2nd return. For those of you with PoolCrete bottoms or floor drains and two returns, what is your opinions about these and do they make the pool more enjoyable and less work? I also would like to add a Safety Winter cover like Inground pools have. We have wood decking surrounding all but one side as you can see in the picture. Could this type of cover be installed here?