HOW do you partially drain a pool?

[west1745]

If you have a DE or sand filter, you can backflush the filter to drain the pool through the main drain. You should have valve(s) to shut off return flow from your strainer(s). If you don't shut off the strainer, your pump will cavitate and stop pumping once the water level drops below the weir. I recently drained 50% of my 15K gallon pool to reduce the calcium hardness and it took less than 3 hours. It took about 8 hours to refill using 2 hoses.

I think I will have to drain about 50% to reduce CYA and calcium. Thanks for your info - I will shut off the fountain and the skimmer and leave the main drain open - can drain out with hose to street.

I guess I have to go and buy salt - not sure how much for about 5K gal.

Thanks for your info and help!