Does vinyl bleaching hurt the integrity of the liner?

[tokmom]

Last evening my son was putting in new tabs in the dispenser when a small chunk of a left over tab fell out of the dispenser. As he picked it up, it broke. He thought he picked up most of the pieces, but parts of them were left behind or were swept away and then settled in one spot. Now we have 4 or 5 dime sized bleached areas on the floor of the pool. Will this hurt the integrity?
This probably wouldn't have been a problem otherwise, but we turned of the pump because a lightening storm was approaching and I didn't want anything fried. I'm thinking had we left it on, it would circulated until dissolved.

For the record, said child/son is 24, so I wasn't letting a small kid play with chemicals.

[PoolDoc]

Now we have 4 or 5 dime sized bleached areas on the floor of the pool. Will this hurt the integrity?

Acidity damages vinyl liners; chlorine bleaches them. Trichlor tabs are a highly acidic form of chlorine. So, yes, it both bleached and damaged your liner. Will it be enough damage to cause problems?

That, I don't know. Usually liners fail at stress points or seams, not in unstressed flat areas.

But, it would be a good idea to keep a liner patch kit on hand. That way, if you do get a hole in the liner -- where ever it shows up -- you're ready to go.

[BigDave]

And the bleached out spots give you a good first place to look if you do start losing water!

[AnnaK]

It's my understanding that cyanuric acid is a 'weak' acid, not like sulfuric or hydrochloric, so its ability to damage vinyl may be minimal.

[PoolDoc]

It's my understanding that cyanuric acid is a 'weak' acid.

True. And, dumping cyanuric acid on a liner probably won't do any damage. John A. Wojtowicz reports that the pH of a saturated solution of CYA is 4.5 - 5.0 -- not good for a liner, but not panic time, either.

However, various sources (for example, here) report that the pH of a saturated solution of tri-chlor is around 3.0, which is definitely worse. But, it's worse than that. The zone under a trichlor tablet not only contains dissolved trichlor (pH 3), but the trichlor releases chlorine, which at that pH forms a mixture of dissolved chlorine with other things. And chlorine in water at pH 3.0 is VERY corrosive.

[AnnaK]

Ah! Thanks much for the link and the clarification.