Frogspawn and Duncan not extending polyps

[ryguy886]

So recently one of my frogspawn colonies and two of my duncan colonies stopped extending their polyps. This has been going on for over a month now and they only ever slightly start to extend then immediately recede. They don't seem to be dying, but not eating or extending????

Any thoughts? This started shortly before I switched everything to my new 285 gallon tank. All water parameters are perfect (0 ammonia, 0 nitrite, <5ppm Nitrate, Cal 420, Mag 1200)

I am at a loss for ideas on what it could be? I have tried to spot feed to see if I can get them to extend to eat but nothing???

TIA,
Ryan

 

[idisc]

Check your alkalinity levels..Lps do this when that is low.

 

[Fish Biscuit]

Check your Alk & your Mg is low, Mg should be closer to 1350