http://www.swimpool.com/category_Swi...Pool_Algae.htm
http://www.swimpool.com/category_Poo...Chemicals_.htm

If you are sure that you have high CYA, and are sure you haven't used any United Chemical products (or other products containing bromide or bromine), we are in uncharted territory. The only thing left to do is a full blown test comparing your pool water with both stabilized and unstabilized tap water. You'll need 3 identical clean buckets that hold at least 3 gallons (and you'll have to clean them again), some liquid stabilizer, some bleach, a set of plastic measuring spoons down to 1/8 teaspoon, and a clean 1 gallon milk jug.

Lemme know when you have those items.

Given the circumstances, it's the only way to establish that you have some unknown 'bad actor' in your pool. If we do establish that, you'll then have to hire a pool service guy to help you drain and refill it safely.

In theory, you could send your pool water off to a water analysis lab, but we don't know what you are looking for, and the sort of analysis that would help in these circumstances would start at over $1,000 and go up from there.

Ben