After Partial Drain - Time to Get Balanced, Need Help

[jasongreenberg]

So I just completed a partial drain and refill because of a very high CYA level. I drained about 45% of the pool. I want to make sure I will get things right this time to avoid getting a high stabilizer level again as it's a real pain to get it back down.

So the pool is still blue, it has been off for a few days now, but I don't see any green algae or anything out of the ordinary, so should I shock the pool first before I start chlorinating again or should I test first after the refill and see if my combined chlorine is over 0.5? My pool store said I should shock every week but I think I don't need to shock unless my CC level gets over 0.5 right?

I want to be cautious with the stabilized Chlorine pucks to not raise my CYA levels too high again, so I am planning on very slowly bringing my chlorinator up every day until I reach the right chlorine level ratio that's relative with the CYA level that I get after the shock. So I'm thinking maybe it's a good idea to shock to keep things sanitized while I bring up the chlorinator? Does this sound like the way to be moving forward from my situation? The Chlorine pucks that I'm using are stabilized "Club Pro - King Size Pucks" 100% Trichloro-s-triazinetrione (Available Chlorine Content = 90%).

My Levels before the partial drain were as follows:

FC = 3
CC = 0.5
TC = 3.5
PH = 7.6
TA = 175
CH = 175
CYA = 146

Thanks for any help!

 

[Mr Bruce]

How did you test a CYA of 146?

You should not use those pucks at all. Even if we believe that 146, you are still looking at CYA ~75 which is super high. Each puck will just bring it up more.

Lastly you should stay out of the pool store.

 

[jasongreenberg]

I used a k-2006 to test the CYA and the pool store test confirmed it.

So what should I use instead of the pucks? I just bought a huge tub of them...

 

[Mr Bruce]

Pool store testing is notoriously inaccurate, especially CYA.

Here's a good article Pool School - Recommended Pool Chemicals

 

[jasongreenberg]

Ok, thanks! I have been looking into liquid chlorine/bleach and will be giving that a try and will keep my chlorine pucks for the future if I ever need a bump in my CYA.

I'm still confused on whether or not I should shock once my refill is done. I bought a tub of shock that has 65% Calcium Hypochlorite, but I'm not sure if it will add stabilizer which I don't want to do.