I would do that, as painful as it is. Technically you could SLAM it at CYA of 80ppm, but it's going to be even more painful and quite expensive. You need lots of FC, which means lots of bleach, and it means FC will disappear faster on top of it. Another partial drain/refill should get you to a better place. This time, vacuum to waste!
If you need encouragement, realize that the previous CYA of perhaps around 100 could have meant much higher than that, so at least now you can be more sure of the number!
Argh, okay! I do indeed need encouragement, but my faith is unwavering!
Lol, that's actually the first thing I thought! "Well, at least now I can vacuum to waste!"This time, vacuum to waste!
Richard320 said:If the vacuum won't seal tight to the skimmer to let you vacuum to waste, try a few rubber bands around the collar so it really gets squeezed in. If you vacuum out as much sludge as you can, that means less chlorine will be needed so you'll recoup some of the cost of the water.
Thanks for the tip! The vacuum is actually pretty tight on the skimmer. This pump has pretty decent suction/flow.
Here I go again!