It's here...

With a CYA of 100, (and it actually could be much higher than that) a chlorine of 2 ppm is not nearly enough chlorine to kill any kind of algae. We can't rely on the test strips to give accurate enough readings to treat water problems. You're going to need a drop-based kit that can test CYA, pH, Cl, TA, and CH. The K-2006 is the kit we really recommend, and is the one Watermom already suggested in her post above. In order to figure out how high your chlorine needs to be to kill the algae, we need a good CYA number. You can try getting a pool store to test for it, but make sure they're not using strips to test, otherwise, it's a waste of time. If you can, check your WalMart and see if they have the hth 6-way drop kit. It has a CYA test in it, but only enough reagent for about 3 tests. I would take a sample of your pool water, dilute it 1:1 with distilled or tap water, test that, then multiply your result by 2. Give us that number, and we can help you go from there.

Also, please fill out the pool chart that Watermom posted--the blue title is the link, just click on it and fill out the requested info.