Low CYA just starting out

ncbrit

LifeTime Supporter
Mar 31, 2010
77
Western North Carolina
So we opened the new pool in the last couple of weeks, and so far the water has been ultra clear by me measuring TCs daily and adding trichlor tabs that came with the pool when the TC level gets low.

First tests with my new TF-100 show everything being close to recommended values, except CYA which is extremely low. I can still see the dot with the tube filled all the way. It's milky white and almost not visible, but I still see it. The PB added a whole tub of stabilizer at opening, but apparently this wasn't enough.

So my question is, I have a whole tub of trichlor tabs which the PB supplied in the deal, so should I continue using those and keep an eye on CYA as it raises, or should I get the CYA level up now, and use liquid chlorine, reserving the trichlor for vacations, etc? I'm currenty adding a tab every 2-3 days.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
It is good, though not essential, to use trichlor for at least the first month after fresh plaster is applied. Trichlor raises chlorine, raises CYA, and lowers PH. With new plaster you usually want all three of those things, so trichlor is very handy. Later on, when the CYA level gets up to something higher, trichlor will not be such a great choice. But for now it is great.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,880
Silver Spring, MD
Ah, then trichlor isn't so convenient because you need to keep raising the PH back up to compensate of the reduction in PH from the trichlor. You can use trichlor if you want as long as you keep an eye on the PH and raise it as needed and stop when the CYA level gets to the right place, but I would add CYA manually and use bleach.