Montipora digitata - grows but polyps never extend?

[jkrohn]

I've had digitata a few times and it seems no matter what I do I just get zero polyp extension. I've tried moving them to high and low light, high and low flow, nothing seems to matter. Coloration is good, they are growing (slowly), just no polyps out. All other corals (SPS, LPS, Zoas) are great.

Same behavior out of Forest Fire, Bubblegum, and Contraband.

I thought maybe a pest, so I've pulled and inspected them, couldn't find anything. Did some dips and nothing came off of them, no effect.

Latest ICP came back fine: https://www.triton-lab.de/en/showroom/icp-oes/220089

Params:
Alk: 8.35
CA: 470
MG: 1352
NO3: 9.9
PO4: 0.09

Any thoughts on things to try different or check on?

 

[KrisReef]

They are not hungry and they get enough nutrients from the water column and light so they don’t need to feed.

 

[Sdoutreefer]

I've had digitata a few times and it seems no matter what I do I just get zero polyp extension. I've tried moving them to high and low light, high and low flow, nothing seems to matter. Coloration is good, they are growing (slowly), just no polyps out. All other corals (SPS, LPS, Zoas) are great.

Same behavior out of Forest Fire, Bubblegum, and Contraband.

I thought maybe a pest, so I've pulled and inspected them, couldn't find anything. Did some dips and nothing came off of them, no effect.

Latest ICP came back fine: https://www.triton-lab.de/en/showroom/icp-oes/220089

Params:
Alk: 8.35
CA: 470
MG: 1352
NO3: 9.9
PO4: 0.09

Any thoughts on things to try different or check on?

Your fluoride and iodine is low. Try correcting those and see what happens.

Correcting Iodine helped my PE on all SPS. I have a 48ish gallon system and do just 1 drop a day via AF's AF Build.