Water Gardening: Raised pond built with cut stones, 1 by FrillyLily

FrillyLily wrote:
Here is today's photo after alot more digging.
I plan on digging deeper over about 1/3 of the remaining floor area, so there will actually be 3 levels of depth.
I know the compost, loose stuff on the top foot or so will have to be dug out around the pond and have clay put in, in order to support the blocks. I will level the ground area out around the edge and lay block all the way around.
Then another layer of block will be added around the top.
Then I plan on lining with sand, carpet and a liner.
With the pond being 6 foot wide (the actual water surface, not counting the stones)
still wondering if the water will have enough pressure to hold the block (and clay under that) in place. OR if the ground will be stronger than the water pressure and cave in? I know its the same question I just asked :) but I thought an updated picture might spur some fresh thoughts on it.