Most of us have heard this argument against the FC/CYA ratio; FC over 4ppm will damage pool equipment. This is even included as a clause some equipment warranties. We all know this isn't true as long as there is CYA in the water.
But I'm not asking about SLAM FC levels. The situation is that I am working with a 120k gallon commercial pool that gets drained every single season. Due poor management of chlorine deliveries, we are stuck with about 80 gallons of liquid at the end of this season, and I am trying to figure out what to do with it.
The stenner pump is a bit oversized for this pool, I generally only keep it at a 1.5 or 2 to maintain 3-5FC. The dial goes all the way to 10, and it would deplete the 80 gallons in a day or two if I cranked it up. However, I could see the FC easily getting into the 40-60ppm range doing this. Could that damage any pump/equipment? There is about 40ppm CYA in the water. Alternatively, I thought about slowly diluting and draining the remainder somehow. How would you handle this?