Designed and built it themselves. Took em about two months, working in their off hours. The plastic inside is from a damaged 1000 gallon water storage tank. I'm assuming they put the boards around the outside to give it some strength and stability. I don't yet know much about the water pumping system, but the pictures I got this morning show what looks like a little dinky 25 sq. ft. filter............... no wonder they say they're having water clarity problems...... I'm going to have to call my PentAir rep on Monday and see if they'll donate a 100 sq. ft. filter.
After that, they started getting creative :-). I was wrong about them having installed an air blower. What they actually did was run a line from an air compressor! (I got a pic if interested)... For heat, they got a heated power washer from the motor pool and run 1/3 of the circulated water through it........... Yeah, I got those pics too.