Yes. Quit using the tabs and just use bleach for your source of chlorine. Post a full set of numbers and somebody here can advise you better. BTW - the pool girl is wrong about 150 being the highest that the cya can go. And, unfortunately, the only way to lower the cya level is to do a partial drain. With yours as high as it is, it would take several partial drains to get it to a more manageable level. You don't want to totally drain a pool at once, however. You may not want to drain now, but you'll certainly need to in the spring upon opening if you opt not to do it now.