Sulphuric acid in CYA

[dawndenise]

I heard that Wal-Mart had a much better price on CYA than Leslie's ($13 vs. $20) for 4#.

After getting the product home, however, I noticed that the WM brand (HTH) has 96% CYA and Leslie's has 99%. Of more concern to me however, is that the WM brand has a side listing that states ingredients as cyanuric acid, SULPHURIC acid and water. The side listing is for EPA numbers...the main ingredients listing makes no mention of sulphuric acid. Leslie's brand has no mention of sulphuric acid anywhere on the container.

Do I want to use this or should I return it? I realize it can't be a whole lot of sulphuric acid, but why would I want sulphur in my water?

Thanks for any advice...

[dawndenise]

I realize it can't be a whole lot of sulphuric acid, but why would I want sulphur in my water?

The dictionary even mentions "heavy, oily, and corrosive" when talking about sulphuric acid.

[chem geek]

Sulphuric Acid (also spelled sulfuric acid, H2SO4) is essentially the same thing as found in dry acid (sodium bisulfate, NaHSO4) except Sulphuric Acid is a stronger acid than the dry acid. In the amounts found in your product, it will add a small amount of sulfates to the water, but not enough to worry about. Even your fill water will have some sulfates in it. I wouldn't worry about it. Only using dry acid or more pure sulphuric acid on a regular basis (or non-chlorine shock, for that matter) would add a lot of sulfates.

Just realize, however, that CYA itself is acidic so this product with sulphuric acid in it is even more acidic so be sure it does not come in contact with a vinyl liner. Either pre-dissolve it or have it in a panty hose sock over a return with the pump running.

Richard

[dawndenise]

Richard...thanks for the reassurance. Vinyl liner is not an issue. I'll consider using the product, but may go back to a more pure form of CYA after this is gone. I prefer to not intentionally add anything to the pool that doesn't have a good purpose.

[mariner09]

I've used the stabilizer from Walmart this season and had no problems. My CYA is about 30 in a 20k gal IG vinyl pool.

[dawndenise]

I've used the stabilizer from Walmart this season and had no problems.

Good to hear of actual experience having no problems...

[CarlD]

I am more surprised that the CYA from WalMart contains water than H2SO4. Water? In a dry powder?

I don't get it.

[dawndenise]

Hi Carl...
Yeah, this product 'tis a puzzlement. The front "Active Ingredients" list shows Cyanuric acid 96% and Inert Ingredients 4%.

Then, way over near the bottom on the back it lists the product's California registration number and below that is...Contains: Cyanuric acid, sulfuric acid, water. Each ingredient has a CAS# (whatever that is) associated with it, including a number for "water."

Container contents definitely sound dry to me when I shake it.