My Duncan's ok?

When I bought these Duncan's about 8 heads where gone and the rest were doing very badly, wouldn't really open. Since I've had them for about a month I've started spot feeding them 3x a week. I've noticed I've lost about 3 heads since I've had them in my tank but the other heads are now doing awesome!! So it seems. It looks like the flesh around the skelly is receding but they are open all day. Looking for alittle explanation on what I'm seeing here.
This is how they look throughout the day.


This is what I'm seeing after lights out.


If there receding would a dip help?? There under 3x 250w MH, 8inch above water. Duncans are in middle of tank, medium-high flow, calcium 560, dkh 8. Po4 0, temp 77.5, sg 1.025, nitrate 0, amm 0, ph 8.1 morning, 8.4 lights out,
Had a fish die a week ago, woke up to a skeleton, check para and no amm or nitrates. Maybe a spike during the night?

Any Ideas here? Thanks

 

Duncans are similar to Euphylia. I would say Moderate flow.(They do not like too much) I moved mine to the bottom of my tank when they weren't doing well and they have come back nicely. You might want to try lowering them some. Dipping couldn't hurt but I would try relocating them first to see if it helps.
With all that being said if they look like the top picture during the day I would not worry too much they look healthy.

 

They do not need a lot of light, as Vinny posted I would try a different location, starting with lower for the tank.

Also check to make sure your SG is indeed the correct value, I have found duncans to be very hardy but sensitive to swings in SG values.

Why is your Ca so high?

 

They naturally retract at night and basically any time youbwant to show someone how pretty they are

 

IME I agree with what's been said~Duncans prefer low to moderate lighting and low flow. I too question your high calcium, or is that a mistype? Personally I wouldn't dip it. They look very nice

 

Vinny and Corailine pretty much covered it. Duncans are like the canary in the coal mine- they are usually the first to show signs that something isn't right. Yours may just need less light, but the right side doesn't look real good. They are sucked in a little too far. Duncans don't like high mag, or swings in alk. Otherwise, they are easy to grow. That's a nice colony, BTW!

 

My calc wasn't a typo, I myself am confused. Nothing has changed in regards to dosing etc, I checked again and refractor says 1.025sg, im doing my normal weekly tank maintenance and am going to take some water down to double check my para, my test are not old but I wanna be sure. I tried testing my mag but seems you have to be a chemist lol ../ughhhh\.. Hate that test!!! ok I will move them to the bottom of the tank, light flow there. Thanks for your help, wonderful people on here!! Karma ++ to you all!

 

It almost looks like flatworm bite marks near the center of the skeleton. Can you get a closer picture? What kind of fish do you have?

 

So I just check my para on my new batch of water I have ready and my calc level is coming back at 620... Gonna pick up a new test kit.. Ro/DI 0tds...Using kent marine salt

 

What are you feeding them?At first I fed my Duncans mysis and brine shrimp.They didn't seem to sprout heads or branch off until I started feeding them silversides.I started out with 8 heads...now I have over 16 heads.Might wanna try it.. Also if that's not a typo..you cal is way too high!!!

90 GALLON DISPLAY
IN DISPLAY TANK;

180 LBS FIJI PREMIUM LIVE ROCK
95 LBS LIVE SAND
(2) 50 GPH POWERHEADS(CARBON STUFFED)
(2) 1300 GPH POWER HEADS

LIGHTING IN DISPLAY;
T5 NOVAS 48 INCH(6 BULB FIXTURES)
48 INCH MARINLAND L.E.D REEF LIGHTING(18K)
48 INCH (24) BLUE LED MOONLIGHT

30 GALLON SUMP
IN SUMP;
40 LBS LIVE SAND
15 LBS FIJI PREMIUM LIVE ROCK.
35 LBS REFUGIUM RUBBLE
PHOSBAN REACTOR(150)
10 WATT U.V STEROLIZER (DONT HAVE AN ICK PROB)BUT BETTER SAFE THEN SORRY
CORALIFE SUPER SKIMMER(120)
(ELITE) 200 WATT HEATER
(10)MANGROVES

LIGHTING ;
IN SUMP
30-90 WATT FLOOD LAMP

FISH
SAILFIN TANG,YELLOW TANG,BLUE HIPPO TANG,DIAMOND WATCHMAN GOBY,SIZZORTAIL GOBY,BLUE DAMSEL(6) BLUE GREEN CHROMIS(4)ENGINEER GOBY

CORALS AND INVERTS
BLUE RICORDEA,SEBAE ANENOME,DUNCAN POLYPS,BROWN BUTTON POLYPS,RED AND PURPLE MUSHROOMS COLONY(6) SKUNK SHRIMP (3) CAMEL SHRIMP(6)PEPPERMINT SHRIMP(8)MEXICAN TURBO SNAILS,(6)CERITH SNAILS,(4)ZEBRA SNAILS(5)RED LEGGED HERMIT CRABS,(5) BLUE LEGGED HERMIT CRABS,

IN SUMP;
(2)GREEN EMERALD CRABS
(5) BLUE LEGGED HERMIT CRABS
(5) RED LEGGED HEMIT CRABS



TO tHoSe WhO rOcK...WiTh A fiLTeR sOcK.....
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