Thanks, I was wondering about getting the level correct; I like the PVC platform idea. I skimmed quickly all the way through looking for plumbing issues. From what I can tell, the real disaster was just a lot of fish deaths (without using strict copper/treatment/QT process)? On the plumbing side it looks like mostly a complete success unless I missed a page; just that one stock tank developed a crack and then a bulkhead failure (but I have read everyone using these tanks recommends drilling out and replacing the bulkhead, so maybe that could have been prevented).
Concerning about the cracked bottom though, it looked like you did go to good lengths to support with cinder blocks and plywood. I wonder if it was just defective; I mean, these things are made for outdoor use- summer sun, winter, sitting on grass and mud. I still have to figure out what to buy or build to get it off the ground though, so that's a good lesson to be extra thoughtful.