I agree with Watermom. As you help them finish the algae battle ( lose almost no FC overnight and no CC ) start transitioning them to taking care of the pool themselves. Encourge them to start an account here and get a K-2006. They will be able to use the water they have this season - they'll need to run appropriately high FC levels for thier CYA, but no need to dump all that crystal clear water. Thanks for helping your neighbors.