Process of elimination, they were doing great before you fragged them, then moved them to a new tank, with different parameters I presume and different lighting.
1. How long were they in the bowfront?
2. Did you ever have this problem in that tank?
3. You fragged them, which can be fatal if done wrong, which I don't think you did. Sounds like you you knew what you were doing. Fragging is always stressful.
4. Did you test the parameters in both tanks before you moved them to the second tank? If you didn't, you really should have. Why? Fragging, gluing, moving, out of water, into a new tank, different ( reduced lighting, which won't harm them, but another adjustment for them to make after the transition, all of which can and will cause a delayed response in expansion.
5. After you placed them in the frag tank, did you turn on your main lighting source? If you did, you really shouldn't have. The last thing you want to do once the transition is made, whether you are fragging or not, is to blast a stress colony with any lighting other than actinic lighting. Even moon lights are better than a daylight bulb. Giving them but one day to acclimate can make a major difference in their appearance the next day. Been doing it for years and it makes a big difference in waiting just that one day.
A water change loaded with potential trace elements will (almost) always serve as a major pick-me-up for any colony in distress to a certain point. For example, if you are dealing with a major outbreak of BI, a water change isn't going to make a different until you treat the source of the problem.
If they are melting to the point where they have already lost their tube like structure, they aren't coming back. By that I mean they are pinched so bad and shading so to speak, this is a colony that middle stages of decline/failure. I would scrap of the dead, collapsed, melting remnants and focus on the polyps which seem salvageable. After the scraping away of any dead, dying or decaying flesh, follow up with an iodine swab of the surface area of the rock with Lugols and a Q tip. Dip the rock in some tank water and place back into your tank. Anytime, anytime you remove a colony to perform surgery, excision etc, you want to place it back into the place it back in the same place or just inches away from where you took it from. Not allow it to touch anything else as it heals. Flow.......Flow.........Flow.........is terribly important when replacing also. Corals will tend to slim after removal and replacement after a surgery so to speak. The current will aid in the blowing off and/or removal of any slim or expelling that may occur. Keep the tank dark at worse, or run your actinics or moon lights only for the first or second day. None of your corals will suffer as a result of doing this.
If I haven't talked you and myself into a circle already, LOL, sounds like it was a combination of stress, environmental shock/ parameter compatibility, stressed from daylights turned on too soon, polyp damage, or the fragging and moving to a new system all in minutes. I wasn't there, so I can't say for sure, just wanted to give you some possibilities. I wish you the best my friend and I hope they turn around for you.
Sorry for writing a book.
Mucho Reef
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