scootchu-

I suggest that you tackle one thing at a time and stay focused. Metals make a mess but they can clear up pretty quickly and can be controlled. Focus first on getting your CYA down (Like you are doing). Keep in mind that a half fill (using simple math) will take it from 110 to 55 and I (personally) think that is still pretty high. Doing a partial drain/refill a 2nd time would get it somewhere I like better, especially if you may also be dealing with metals. Keep in mind that metals react with High Chlorine and High PH so, in theory, if you need to shock and/or maintain at higher levels of FC due to your CYA number there may be a higher likely hood of a metal reaction.

If you really think you are dealing with metals, then I suggest the following:

When you do your refill and get your CYA down, Get your PH to about 7.0. Get your FC to about 1. Add about 1.5 to 1.75 qts of Pool Magnet or HTH Metal Control, let it circulate in the pool overnight. (don't add the product during sunlight).

Next, Vaccum if needed. Then begin to raise your FC to Shock level see BestGuess guide post. keep it at the appropriate level until it holds overnight, I'd even give it one extra night if you can be patient enough. Kill the 'pool livestock' and make sure its gone.

At the same time keep monitoring your PH and keep it low 7.0 - 7.2. **If and only if you believe that you are having a metal reaction due to your shock treatment, after you've completed 'shock therapy' let your chlorine level drop to somewhere around 1-2 and put some more Metal Control in, about the same as before, vaccum again and bring your FC back to the appropriate range.

I'm not a forum expert but have been dealing with metals.