bubble coral

[Myka]

Bubble corals can be finicky, and they really don't like nitrate and phosphate in the water. If the flow is too high they will retract as well, but it sounds like the coral has been in this position for some time now. If the powerheads blow sand onto the coral it can settle in the center, and start to kill the coral. Using a turkey baster to blow the sand out daily will help it come back if this is the issue. I would be willing to bet it is less than ideal water conditions though. To help bring it back start feeding it daily with 6 or 8 Mysis shrimp. It should come back fairly quickly with aggressive direct feeding of larger meaty foods.

[68shelby]

did my water test today.
ph 8.3
nitrate 1 ppm elos kit
calcium 420ppm salifert kit
nitrite 0
ammonia 0
temp 80 does not fluctuate past 81 or below 80
kh 80
specific gravity 1.024
no algae in my tank so I seldom test for phosphates.
I do on a regular basis stir up the sand, so he could have gotten sand on him, I did lightly blow it off of all the rock work and corals, last night however. And I never directly feed him.

[Navarchus]

I do on a regular basis stir up the sand

Why?

what about alk and mg?

keep an eye on your blue tang.....