Duncan coral help

[daplatapus]

ok, I picked up this really healthy looking Dunan coral July 26th. After acclimating it I put it into my 20 Gal cube. It looked great for the first 2 days. Apparently though, the clown fish in the tank didn't appreciate not being consulted first about it's location. The 3rd morning I found the Duncan face down in the sand. I figured it had fallen, picked it up and stuffed the base back into the hole it had been in originally. Not 2 min later I watched as the female clown went over and grabbing the rim of one of the openings pulled it out of the hole and dumped it back into the sand! I've actually since seen her do this with a monti I put in there too
SO, ever since, the Duncan refuses to come out. I've switched location thinking it didn't like something, flow, light etc. but it just won't come back out. It's got 9 heads, it ate when I first got it, but now it won't do anything. I even go check it out at night but have yet to see it out since that 2nd day.
Any ideas?
NH3 - 0
NO3 - 0
NO2 - 0
KH - 8.6
Mg - 1400
Ca - 375

Even though it's in my cube, it's tied in with my main DT so a cumulative 130 ish gallons of water. Everything else is doing good.

I did just change to an LED fixture but have turned down the LED's to almost 20% but still no change. Now I put them where you see in the pic below where they are under a bit of an overhang just in case it's still too much light.

[Snaz]

It is probably POed from the new tank, dumping by the clown and new lights. Give it another week or so as it looks healthy otherwise. Are a couple of polyps buried? That might also **** it off.

[sphelps]

Give it a new spot where it won't be disturbed if you haven't already and try not to move it around. Corals need to adapt to new tank conditions which they can usually easily do but any added stress tends to push them over the edge. A common mistake is constantly moving them around thinking they'll do better in another location. Give it a few days, check it at night as it might come out then. If it comes back out feed it.

[daplatapus]

Yeah, I've only moved it the once. I decided after putting it were it is in the pic I'd sit there and watch, and wouldn't you know it, the clowns started pecking at it
So, I took it and put it in my main DT. We'll try that for a week.

[Enigma]

I have a duncan that is doing very poorly: every time I put it back in my display tank it closes up and loses heads. I think I've finally figured out why: magnesium. It seems to have a very tight window of tolerance for it. Fussy, fussy! It is happy at around 1350.

What is your alk at?

[daplatapus]

8.6, and rock steady. My Ca has been weird the last week or so, but everything else has been spot on for months.

[daniella3d]

I have my mag at 1500 right now and all my duncans are doing great. Maybe it is something else? The only time I have seen a duncan died was in a tank with a lot of nitrates. I actually thought they were nearly undestructible before as they are very resistant.

One of mine is nearly 3 year old and has grown too many heads too many times.

They do need lights and they do need food. Mine really swell large when the MH is on.

Once I had one did the brown jelly and cought it in time. I took it out of the water and put peroxyde right on the affected area and it healed in 2 days.

Originally Posted by Enigma

I have a duncan that is doing very poorly: every time I put it back in my display tank it closes up and loses heads. I think I've finally figured out why: magnesium. It seems to have a very tight window of tolerance for it. Fussy, fussy! It is happy at around 1350.

What is your alk at?