I've used the Bayers products extensively for all my dips and it is the best dipping method by far IMO. The corals doesn't seem to get stressed either. Even my fire ice echinata don't mid this dip. For Zoanthids I still use iodine though.
Make sure to check the parameter of your make up water and adjust it for your purpose before doing the water change. Sometime I use a lower salinity in my make up water like down from 1.026 to 1.025 when I need to lower the parameter a bit.
I think you have several things that might contribute to the STN, your parameter went rhough some changes specifically mag and alk. We all know corals will get burn tips from spike or dip in alk, but they will also get burn tips from a spike in mag. both of your alk and mag are on the higher...
The cal and alk seems to be out of the optimal balance to me, I think if you lower your alk and raise your cal slowly it will be better.
Also I notice the corals seems to be opening nicely except for the burned edges, this might point to suddent changes of one of the three components...
That stuff is pour on resin, it give you a very nice thick clear glossy finish
If you want a guitar like finish then it's laquer, wet sand 600-grits sand paper, laquer, wet sand 800-grits, laquer, wet sand ..... and after the last coat use a buffer.
I've used tooth paste for my acrylic and it works great, for glass you might want to try a dremil with a buffer bit and some polishing/buffing compound
So I picked up a brown out sps frag, the label was brown out coral and the plug was one of those nice square white ceramic plug. I have a feeling someone was hiding a surprise in this swap because the coral might turn out to be a nice one. I'll take picture as soon as it colors up, so far it...