This brings up a point that concerns me since using non-Clorox household bleach in my pool. I'm in Latin America, so the choice is pretty much off-brand bleach. After adding a gallon one night recently, the following day some swimmers reported a burning sensation or stinging in the eyes. I won't receive my Taylor test kit for another week, so I'm not able to report on any test values at the time.stev32k said:Wal-Mart and other store brand bleaches are a chlorine/caustic plant by-product. Chlorox is the only brand I'm aware of that actually makes a household bleach on purpose. The off-brand bleach is made by adjusting the chlorine concentration of a chlorine/caustic solution that is produced when an imbalance occurs in the chlorine/caustic plant (usually because of selling more caustic than chlorine one week then more chlorine than caustic the next). No attempt is made to control the caustic content (within reason) and as a result the excess caustic can and does very widely from batch to batch. That's why you will sometimes need to add acid after using a store brand and sometimes not. I stopped using Wal-Mart brand because it was costing more to buy the hydrochloric acid than it would to buy the chlorox.
The word caustic has been mentioned. Something that is caustic can burn the skin. Could my non-U.S., off-brand of bleach be responsible for this burning sensation due to a high concentration of lye? Lye increases the pH. In general, does a high pH in swimming pool water cause stinging in the eyes?
I've just learned today that one of those swimmers that experienced this effect in my pool, also experienced the same effect today in a public pool, where they also reported a strong smell of chlorine. I've learned from reading this forum that that is not due to too much chlorine, but rather to too little free chlorine in the water.
I don't know if the following belongs in a separate post, but my original use of bleach a few weeks ago was related to the appearance of some green algae. I added a gallon and the green algae disappeared completely. What I have now is black spots on the pool walls and floor. I'm nearly certain this is algae, too. But when I added another gallon of bleach at night, and then checked the following day, the black spots were still there. This was five days ago. Yesterday, we added a gallon of muriatic acid thinking that maybe the pH was too high. No effect. [From reading this forum, shocking the pool with chlorine is how to deal with that problem, but I'll wait for your reply to this post. Again, still waiting on the test kit. Floundering in the dark here.]