Green pool now blue after shock, what now?

[aylad]

If you'll look at the best guess chart in one of my above posts, it tells you that to shock a pool with a stabilizer (CYA) of 75, you need to raise your chlorine up to 20 ppm and keep it there by testing and adding more 2-3 times daily until the water clears up again. To get to 20 ppm, it will take 11 gallons of 6% bleach. After that, when you're re-testing to add more, each 1/2 gallon of bleach will raise your chlorine by 1 ppm, so you can use that as a guide to figure out how much more to put in each time. Keep the filter running, brush the pool daily. Keep it at 20 ppm until the water clears, you have no combined chlorine, and you're not losing any chlorine when testing at night after the sun is off the pool and again in the morning before the sun is on the pool. After that, then you can let it drift back down, just like you did before. However, this time, DO NOT LET THE CHLORINE DRIFT BACK DOWN BELOW 5 PPM. Because your stabilizer is so high, you must keep it higher than 5 ppm to keep from having to repeat this cycle over and over again. This means that you must test the water daily, and add chlorine (bleach) as needed (probably daily, or at least every other day) to maintain your chlorine levels and not let them go to zero again. This is an ongoing process, not a one-time cure.

You want to enjoy your pool, not just spend the summer treating it!

Janet