There is no plastic or liner. We pump water from one of our stock tanks to fill it up. I don't mind you asking but honestly I don't know. My DH and brother in law did all of the digging with a back hoe and tractor and they used rocks from our back pastures. The pump is an old used swimming pool pump. My DH says if we were to pay for the digging it would have cost around 3,000.
No liner. Do you have a filter? Ours is still a work in progress. The top part is the original that was dug deeper when we dug the bottom part. For some reason, the bottom isn't holding water. Would love to see pictures of yours
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X2 Good luck and keep us posted if you can.