Pumps were inaudible - I mean a birthday party full of 5-8 year-olds isn't a quiet environment, but: - the pumps were submerged - I put a rubber mat on the bo

Pumps were inaudible - I mean a birthday party full of 5-8 year-olds isn't a quiet environment, but: - the pumps were submerged - I put a rubber mat on the bottom of the big black rubbermaid container, though the thinking here was to stop them bumping around rather than noise per se - and the connection to the raceway was via flexible tubing, so there was no vibration transfer. Overall I'd expect the pumps to be one of the least-loud parts of the system , the flowing water was way louder, and that's not very loud. I've since bought myself a 4'x3' laser-cutter [1] (and many projects have been jointly undertaken as a result :), and the plywood has been satisfactorily repurposed (one side is fine, so I just made sure the side I had painted previously wasn't visible. There's lots of projects where re-using is pretty simple :) [1] https://i.imgur.com/IiIvFFv.jpg https://i.imgur.com/IiIvFFv.jpg