CYA: Sock vs Filter

[shep377]

Wondering about cons and virtues of these methods...

• 
  1. Slowly pouring into skimmer to run through pump and settle on sand in filter. Over a few days, it can dissolve from there
  2. Tube sock filled and placed in skimmer basket. Will dissolve from there.
  3. Tube sock hanging in water, in front of skimmer intake. Dissolves into water, then most will be immediately circulated via skimmer intake.

Option 1 and 2 seem the easiest. Option 3 seems to mean a pole braced over the edge to hang it from so a little more hassle. Option 1 means no backwashing until you are sure that it has all dissolved. Option 2 and 3 seems to be both talked about in the forums...

Just for fun, I asked a PS and they said, "Why would you use a sock? That's just silly :blah: " (see, it was fun)

What's your opinion?

 

[Richard320]

1) If you need to backwash for any reason,. your expensive CYA granules are gone.
2) Like it or not, stabilizer is an acid. pH will go down some when you add it. Unless the pump is running 24/7, you're going to have a pocket of very acidic water in the skimmer and the plumbing adjacent to it.

 

[elwood58]

Best is a sock full in front of a return. This avoids a highly acidic skimmer basket. Second best would be a sock in the skimmer. My last choice would be layering on top of sand. If you wind up needing to backwash in less than 2-4 days, your CYA gets flushed out.

 

[JasonLion]

Pouring CYA into the skimmer too quickly can damage things. That is rather rare, but just often enough that we don't recommend that approach.

The "highly acidic skimmer basket" issue is not an issue. CYA isn't that acidic.

 

[shep377]

Thanks JasonLion. While you are adding CYA via sock-in-basket, is it safe for the kids to swim in the pool? Is there a general rule you folks recommend like:

• Add Bleach, wait 20min before swimming?
  Add MA, wait an hour before swimming?
  Add CYA via sock, swim all you want, don't stick your arm in the skimmer?
  Don't swim when TC is above XXX?

These would be good standards to practice if I knew an answer...

 

[Richard320]

30 minutes of pump running should be enough to get things dispersed so swimming is safe. A little brushing will speed it up even more.

I personally wouldn't worry about the CYA hanging in there, just tell them hands off. It dissolves slow.

It's safe to swim up to shock level, which varies with the CYA level of your water.

 

[shep377]

Thanks Richard320. To move my CYA from 20-55, TPC says I need 2.756kg of the stuff. One tub was 1.75kg which I stuffed into a sock, tied it and put it in the skimmer. It has been a few hours and it doesn't seem to be going down fast. Once it's done, I have another full sock to follow... and that will bring me to 55! Wait a week and again... slow process!