I personally can't think of a reason why the CYA couldn't reside just fine in the skimmer with the pump off but there may be one I'm not aware of. The pump will certainly help it dissolve faster so that would be my choice...to leave it on.
I let my filter run on it's normal schedule, (2) 6hr cycles, and it takes about 4 days for my sock to empty. Just make sure you don't clean your filter for about a week. CYA is slow to dissolve and some will be in your filter until it completely dissolves.
To me it makes more sense to keep it running to get your cya in quicker. The faster its in the quicker your stabilizing. I don't think it will hurt anything but personally I would want my water stabilized more quickly.
I wouldn't recommend that approach. If you pour the CYA directly into your skimmer it'll more than likely all settle on top of your filter and the first time you backwash - poof - out it goes. CYA can take up to a week to dissolve. Consider putting the stabilizer in a sock or panty hose, tie the sock off to a nearby stationary object, like a heavy planter, or chair and let it just twist and dangle in front of a return. It will dissolve in time and you won't have wasted your time and money. If you want, you can speed up the process by squeezing the sock every now and then. Hope this helps you out. Good luck!
I got some HTH brand CYA from Meijer and put it into a sock and threw it in the skimmer. It was really mushy in about an hour, so I hung it in front of my return and in about 2 hours the sock was empty. I only added 2.5 lbs.
My question is, Why did mine dissolve so fast? ( is it because the HTH brand is made differently) and will there be any in my filter so I should leave it running for a few days ?
Sorry if I hijacked this thread, I just thought that maybe the info that the HTH brand dissolved pretty fast could help out someone who wanted fast dissolving CYA.
When CYA vanishes from the sock it hasn't necessarily dissolved. One of the things that happens with CYA is that it first breaks up into tiny grains and then the grains dissolve slowly. If you put a sock in the skimmer, the CYA will break into grains, get through the sock, and go into the filter in a couple of hours. So really that is the same as just pouring it into the skimmer.
I simply pour CYA into the skimmer and then remember not to backwash/clean the filter for a week. If you know that you will have to backwash/clean the filter then you can try putting the CYA in a sock in front of a return. Some of it will still end up in the filter, but not nearly as much.
Thanks for the fast response Jasonlion, I will hold off on backwashing and will also test later on this weekend to get a true reading on the CYA. I went and looked for this topic elsewhere on the forum and learned a ton from you guys about the CYA and how it dissolves slowly. Of course I did this after I posted my questions. LOL Next time I will do a search first!!