I think most good stuff is already said.
This is a hobby and sometimes you find your self alone on that.
There's no reall given explanation what's going on in most cases.
What I know reading all this is that you stripping your tank and you see the effect on your corals.
Zoa's can be real hardy corals compare to SPS (by now you could have killed all SPS in your tank).
I had similar and similar doesn't have to be the same issue, I cut down on GFO and started dosing slowly with ZEO-vit products.
In about a week the zoa's opened up pretty good but most the color came back, now 4 months down the road my colonies doubled in size.
Good luck and let us know how things are progressing.
Btw, the best thing you did so far is asking the reefers on R2R here, there's NO better way to be successful in this hobby than asking and learning from some of the best.
This is a hobby and sometimes you find your self alone on that.
There's no reall given explanation what's going on in most cases.
What I know reading all this is that you stripping your tank and you see the effect on your corals.
Zoa's can be real hardy corals compare to SPS (by now you could have killed all SPS in your tank).
I had similar and similar doesn't have to be the same issue, I cut down on GFO and started dosing slowly with ZEO-vit products.
In about a week the zoa's opened up pretty good but most the color came back, now 4 months down the road my colonies doubled in size.
Good luck and let us know how things are progressing.
Btw, the best thing you did so far is asking the reefers on R2R here, there's NO better way to be successful in this hobby than asking and learning from some of the best.
All the Z&P's have a much deeper color as well. I did start getting some hair algae, so I added 250ml of PO4x4 to my reactor a couple weeks ago. Thanks everyone for your comments, especially Ninjapotamus!!! I plan to continue without biopellets, assuming my SPS, which is most important to me continues to thrive. Here is a bad untouched iphone pic. 
