Acan health problems!! (with pics) - Please advise

[wscttwolfe]

untitled shoot-003.jpg by wscttwolfe, on Flickr

The acan in the middle (on top of the rock), next to that brown algae (anyone know what that is btw?) has been withdrawn up like that for 4-5 days now. At night, there is no tentacle extension. As you can see, the acans on the left and right are completely healthy. I might add that my hair algae is slowly disappearing, not growing, so I doubt that it is causing false nitrate/phosphate readings. I've had this guy for about 2 months now.

Any ideas about what might be the cause?

Just tested water params:
salinity: 1.0245
nitrate:0
phos: 0
ca:420
dKH: 10
mag: ? (test kit empty)
pH:8.2
temp: 79-80, constant

lighting: 8:15 hrs, LED
tank: rsm 130d (34 gallons)

Thanks for the help!

 

[reefer gladness]

That's a hard one to figure but when in doubt a good size waterchange never hurts. Test a test kit for mag when you can obviously but a waterchange should replenish a good amount unless there's an issue with the salt itself (I've had low mag with Red Sea salts before). After the waterchange I'd try to spot feed it and see if it opens up.

 

[whippetguy]

Too much light? Too much flow? Have you tried moving it lower or next to a ledge. Like reefer asked, does it react positively when being fed?

 

[wscttwolfe]

Too much light? Too much flow? Have you tried moving it lower or next to a ledge. Like reefer asked, does it react positively when being fed?

No noticeable reactions when I put a mysis on top of it two nights ago. It was eating 2 weeks ago

 

[reefer gladness]

Has your water chemistry been stable? i.e. no sudden swings in alkalinity or pH? A couple of my acans close up towards the end of the day when the pH tends to rise. Consider taking a water sample to your LFS and have them double-check, especially if you're using the Red Sea test kits they were shipping out with the tanks. Your alkalinity is within the 8-11 range but it's on the high side. It's not really feasible to have both high calcium and high alk, I keep my calcium on the high side between 430-450 and alk on the low side between 8.3-8.9.

If no issues with water chemistry and you've done a recent waterchange I'd try moving it to a place with less light or dim your LED's. It's not really possible to judge the amount of PAR being received with the naked eye. The LED combo of cool-whites and royal blues doesn't appear as bright to us compared to stock lighting because we see green very well and there's very little green in that cool-white/royal blue mix, hence we turn up the intensity until it looks bright to us but the PAR is much higher than with the stock lighting. I have the same tank and built pretty much the same LED kit (before Rapid had a 130 kit). My 130D is a very expensive quarantine tank now but I plan to keep it and re-work the LED mix later on.

 

[wscttwolfe]

All good things to keep in mind. Thanks for the advice. It's already partially under a ledge, so I don't think there's much more I can do in terms of getting it out of the light. Guess the only thing I can do is a water change, and pray

 

[wscttwolfe]

update: so I ended up doing absolutely nothing, and this coral is looking fine now. sometimes, corals are just weird.

 

[whippetguy]

Good news. Sometimes keeping our hands out of the tank is the best answer.