Hmmm, where to start?
I'm not sure how you're applying it but I don't think I understand how you're getting a cloud of gas and killing something.Everytime I see that cloud of gas I wonder what I've killed.
However, if you monitor pH carefully and dont like muriatic, run your pool at 7.8.
No chlorine in three weeks? That's gonna' be a problem. I doubt your pool is sanitized.
Post a set of test results and folks here will be glad to give you some advice on making your pool a little easier to manage.
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