wonder what he was going to do with this tennis ball thing. And was this thing legal, and was it legal to operate it there, spca and bylaws is going to be on him.
I use the smartlife ,tula one's . I use a heavy duty relay with it at my house. I installed one, when you close the metal cover, there is no wifi. They leave the cover open. But they work fantastic.
I once added copper something to trace a leak. After that pool water react bad, went to a pool shop. They told me to removed the water and refill. That was the cheapest option back then.
friend off mine use his dirty water. He got a tank next to washing machine outside, lower of course. water of his bath and washing machine goes there. He then pump that water to garden. But it does not smell so nice. His grass is green.
I would fit a wide pipe[eg 75mm] next to the washing...