The only thing I feel you can do is to tell your customers they must drain and refill to get the CYA level normal. They don't want to? OK, ask them if when they wash their clothes if adding a gallon of detergent cleans the clothes better than the recommended amout on the package. Hopefully, they will say that would be crazy.....perhaps in that lesson you can wise them up enough to realize their pool with 500ppm of CYA is the same as a gallon of laundry detergent in the washer.
Your part in this, in conjuction with the above realization, give them that schedule (add one gallon a day) to keep the pool good until you can return. I would have that number figured out when you advise them that their high CYA is unworkable.
On the lighter side, if you could get an empty 55 gallon drum, wheel that up next to the pool along with two one gallon bottles of bleach. When they ask what the heck is going on, tell them until they drain and refill in order to keep algae for cropping up, you need to add two 55 gallon drums of bleach in the pool....OR, they can drain and refill then around two gallons of bleach should do it a day.......
You are really stuck between a rock and a hard place here because customers are money in pocket, but what to do when the customer who is always right is way off base? Perhaps you can sell them on a SWG system selling it on "no more pucks"........
Bob E.
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