Our cousins are back - kinda (he's military and gone a lot) - and she doesn't know how to maintain the pool. I tested (at the pool store) today and the chlorine was 0.1. The water was cloudy and kinda green. The salt was also a little low. My question - how much bleach would she need to add rather than shock? The pool store said 3 bags of shock and running the SWG for at least 24 hours. Suggestions?