First thing I would do if it were my pool is quit using the trichlor chlorine tabs. They are adding CYA and yours is already a little high. Not a problem but you don't want it any higher. You will need to run a little higher than normal chlorine levels as a result. Take a look at the Best Guess Chlorine Chart in my signature below for the correlation between CYA and needed chlorine levels. (If you already have tabs in there now that are wet, let them go ahead and dissolve but just don't use any more.)

Your TA is a little low. You might want to add a little baking soda to try and bump it up to around 80-100 or so. Work on this gradually instead of one big dose. Maybe a cup or two at a time. Pour it into the skimmer slowly while the pump is running.

How did your CH get to 200? Are you using cal-hypo or have you added any calcium or do you just have hard water?

I would suggest just using bleach for your source of chlorine from now on.

Hope this helps.