I just don’t understand

[Msmelisa1002]

The only time I can see my Duncan open is at night after the lights go out.
The only thing I can figure is ph since it drops at night. Correct?
My ph during the day hovers around 8.2-8.3.
I’ve tested at night and it’s around 8.
Help?

 

[Reefkeepers Archive]

The only time I can see my Duncan open is at night after the lights go out.
The only thing I can figure is ph since it drops at night. Correct?
My ph during the day hovers around 8.2-8.3.
I’ve tested at night and it’s around 8.
Help?

Those polyps look really white, are you sure it's not a dendrophyllia (NPS coral) @encrustingacro?

Can't tell best from the photo but does the coral by any chance have any orange on it?

 

[Msmelisa1002]

Those polyps look really white, are you sure it's not a dendrophyllia (NPS coral) @encrustingacro?

It’s a Duncan.
I also have another one that has been closed.
It’s in another area of the tank with the sameness.
This was it before the tank upgrade.

 

[Reefkeepers Archive]

Have you tried offering food during the day (if it's coral only)


Could a fish be picking at it during the day? Could the light/flow be too strong?


Also when did you move it? Duncans can be moody and may randomly decide to close for a week or so.

 

[Msmelisa1002]

Those polyps look really white, are you sure it's not a dendrophyllia (NPS coral) @encrustingacro?

Can't tell best from the photo but does the coral by any chance have any orange on it?

No orange

 

[vetteguy53081]

The only time I can see my Duncan open is at night after the lights go out.
The only thing I can figure is ph since it drops at night. Correct?
My ph during the day hovers around 8.2-8.3.
I’ve tested at night and it’s around 8.
Help?

Theyre bleached and have experienced at some point too much light which has affected the production of color and energy known as zooanthellae. May be why they respond in low light. Assure phosphate not elevated and feed then 2x a week with mysis shrimp

Some of mine:

 

[Msmelisa1002]

Have you tried offering food during the day (if it's coral only)


Could a fish be picking at it during the day? Could the light/flow be too strong?


Also when did you move it? Duncans can be moody and may randomly decide to close for a week or so.

I feed ab+ once a week. And reef roids once a week.

I have monitored my tank for the pesky fish, inverts, etc for the picking.
No one does.

I have iodine dipped. Also have a wrasse tank.

This has been closed almost 2 months except in the evening.

My par at his level are about 120.
Lighter flow.

 

[Reefkeepers Archive]

I feed ab+ once a week. And reef roids once a week.

I have monitored my tank for the pesky fish, inverts, etc for the picking.
No one does.

I have iodine dipped. Also have a wrasse tank.

This has been closed almost 2 months except in the evening.

My par at his level are about 120.
Lighter flow.

Tempature? What are the nutrient levels at?

 

[vetteguy53081]

I feed ab+ once a week. And reef roids once a week.

I have monitored my tank for the pesky fish, inverts, etc for the picking.
No one does.

I have iodine dipped. Also have a wrasse tank.

This has been closed almost 2 months except in the evening.

My par at his level are about 120.
Lighter flow.

Reef roids raises Phosphates, the very element I mentioned may be elevated and feed mysis instead of Roids and AB+ which raises nitrate and also Phosphates

 

[encrustingacro]

Those polyps look really white, are you sure it's not a dendrophyllia (NPS coral) @encrustingacro?

Can't tell best from the photo but does the coral by any chance have any orange on it?

I'm pretty sure it's a duncan; it's likely bleached. Dendrophyllia have smaller polyps with a lower tentacle count.

 

[MrGisonni]

If your other corals are doing well and all your parameters are stable just move the Duncan Coral somewhere else. And I would go for less light. I would also maybe try a little bit of direct feeding. Sometimes corals don't do well where we put them initially in our scape. A change or scenery so to speak often works wonders.

 

[DanyL]

Duncans aren't easily bleached from my experience.
I've grown them under 500 PAR without any problem, even when I move them from low PAR to very high PAR without any acclimation.

Are you aware of any Alk/Ca/PO4 swings you had in the past month or so?
When it's open at night - do you see the polyps move from side to side rapidly?