I think as long as your pup doesnīt stay in the water long and you clean them, it isnīt a big risk for ear infections and if they arenīt enjoying it they will soon get out.
I think though i disagree that the beach is more damaging. My pup had a little paddle day b4 yesterday and he got a bit sandy but u just need to give them a good brush. I would be careful with chlorine incase the levels arent right in the pool.
Remember a humans PH is different to that of our furry pals, so what chlorine levels may be right for us wonīt be right for them.
It could even give them skin conditions. Whereas sea water is cleansing.
Love Vikki and Rambo
