Colt Coral

[OceanFox]

I recently (about 4 days ago) got a colt coral for my 75 gallon tank (been set up about 3 years)and it's acting odd. It will start the day extended and busy and very nice looking. But it ends the day "shrunken" in (I took a photo of it in sunken mode). Is that normal behaviour for a colt coral? I've read it's a low light coral. I have moderate light (2 175 watt metal halides and 2 110 watt VHOs) but I placed toward the bottom of the tank. Is it getting too much light maybe? The lights are on about 8 hours a day, the halides are only on for half that time. I don't have any high light corals so I don't keep them on. The VHOs are probably due to be replaced pretty soon but the halides have been replaced recently.

Thanks,
OF

 

[MIKE NY1]

Hi OF and welcome,
it's normal behavior for this coral to expand and shrink during during a 24 hr period. I have one that expands during the day and shrinks at night. I have a second that expands and shrinks a couple of times during the day and night. As long as it fully expands it's doing fine. If it doesn't I would give it a few days to acclimate and then try moving it. Colt coral is a name used for a many corals in the family Alcyoniidae because many of them are hard to Id. So knowing this it may be difficult to know exactly what species you have and it's requirements. It will let you know if it's not happy by not fully expanding.

Good Luck
Mike

 

[Tcook]

As Mike said, this is normal behavior. My colt (Cladiella)went through these changes several times a day when I first introduced it. Now, 1 year in my reef, it only closes down at night. I've had it 16-18" under 175 watt MH and 250 watt MH where it did well. Due to its growth, I have moved it to the back where it gets more indirect light. It has done great under both conditions.