How in the heck can someone by pool, put it up, not install the

Villas - How in the heck can someone by pool, put it up, not install the filter, nor put any chlorine or any other chemical into the pool. Then on top of this put kids in the pool in which some are still in diapers? One huge bacteria cesspool. If myself or any other "normal" family put there kids in there they would have ear, eye and throat infections. Unbelievable