Cyanuric acid heated up and dissolved almost immediately

mokonack

Member
Jan 12, 2015
16
Orange, CA
My pool went neglected for a few weeks as our first child was born last month (I added bleach/acid sporadically but not with any precision).

Now I have a bit more time to get everything balanced. My pH was about 8.5, FC 0, and CYA was almost 0 which was a surprise since I had added about 4lbs a few months ago to balance everything. So to start with, I added a half gallon of muriatic acid and put 4lbs of cyanuric acid in a sock in the skimmer. I spent another 30 minutes brushing and cleaning the pool vacuum and went back to check on the sock. To my surprise more than half had already dissolved. I squeezed the sock and it was extremely hot to the touch as if an exothermic reaction was underway. I’ve never seen CYA dissolve so quickly nor had it heat up. Has anyone else had this happen before?
 

mokonack

Member
Jan 12, 2015
16
Orange, CA
Oh Crud.

I always order my CYA on Amazon from the same retailer. I should have looked at the box this time more closely - they shipped calcium instead of CYA. Arghhhhh.

Well, at least now I know what’s wrong but now I have to drain a ton of pool water. Sigh.
 

jblizzle

Mod Squad
TFP Expert
LifeTime Supporter
May 19, 2010
43,238
Tucson, AZ
What do the calculations indicate that you raised your CH to? I would not think it was enough to warrant a large water exchange
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
23,589
San Dimas, CA (LA County)
Oh Crud.

I always order my CYA on Amazon from the same retailer. I should have looked at the box this time more closely - they shipped calcium instead of CYA. Arghhhhh.

Well, at least now I know what’s wrong but now I have to drain a ton of pool water. Sigh.
Probably not.

Use Effects Of Adding Chemicals at the bottom of PoolMath to see how much CH you just added. Probably not as much as you think.
 

mokonack

Member
Jan 12, 2015
16
Orange, CA
My CH has always been somewhat on the high side (~350+). This is also the second time I’ve added 4lbs as I used the same box last time. I unfortunately wasn’t paying much attention last time due to baby prep so didn’t measure CYA after adding.

I’ll let the water turn over and see what the CH is in the morning to determine what to do.
 

mguzzy

Gold Supporter
Jul 8, 2015
1,771
OV, CA
Big pass on the wrong chemical... new Dad's always have something else on their minds!:scratch::sleep:

I had a roomie once try and help with chorinating the pool... he grabbed a jug at random and dumped it in..turned out to be MA.

Congrat's on the new pool user in your house!
 

mguzzy

Gold Supporter
Jul 8, 2015
1,771
OV, CA
I would be wary of that company. This the second report this year of mislabled chemicals from them.
So was the box itself mislabeled or just the wrong item was shipped? I order Puritech via Amazon as well. Then divvy my 25lb order into smaller 8lb buckets for later.
 

mokonack

Member
Jan 12, 2015
16
Orange, CA
I would be wary of that company. This the second report this year of mislabled chemicals from them.
This wasn't a case of mislabeled chemicals, but of a combined screw up - the seller shipped the wrong item and my new dad brain didn't read the box until noticing it dissolve and heat up.