I just checked with someone of a medical profession. The red bumps we all
experience can be caused by a variety of bacteria that can survive high temperatures. The bacteria can cause permanet damage to our skin. The best solution, as I was told, is to drain the water, fill the pools with fresh water, chlorinate it extensively using double of recommended for commercial pools dose, then drain and refill. I'll try to find out how to put chlorine in the water.