Plate Coral Hijinx--Mysterious Movement

[Hgarner]

To all--

 

I have a purple/blue plate coral (for the last 3 months) that has traditionally reacted adversely to the 36w 50/50 day/actinic CF bulb that I have been running in my 12 gal eclipse nano. No problem, or so I thought--I sculpted a little overhang of LR that gave him ample shade, and he has basically been puffed up and happy in the shade.

 

Approx. 10 days ago, I came downstairs to find the plate completely pushed out of his hole (or so I thought) by my clownfish, who had taken to sleeping in the plate's cave. I just assumed the clown was being territorial. I removed the clown 2 days ago (for lots of other reasons) and have had only a skunk cleaner shrimp in there since then, who (a) doesn't hang out in the plate's cave and ( doesn't appear strong enough to push the plate coral.

 

I then came down this morning, only to find the plate completely out of his cave, and also propped up against the side of my LR as though he was trying to climb it. He was also puffed up and happy. The lights had been off for approx. 8 hours, with only a faint LED moonlight as illumination.

 

I've read that plate corals sometimes "walk" by using their inflated flesh, but if I leave him alone, I know he will be burned by the light when it comes in a few hours. Has anyone had any experience with plate corals on walkabout, and if so, have you corralled them successfully? Moreover, I'm somewhat surprised that my plate can't handle the light load in my tank--is there any way to condition them to handle the light so I can keep him out of the shade, where it is difficult to see his colors? I have purposefully not used my lighting array's full capacity (2x36w CF), and I would like to be able to for the beneficial effect on my other corals.

 

Thanks,

HG

[Hgarner]

An update, for what it's worth--

 

3 hours after discovering the plate exposed and puffed up on the side of the LR, he is now deflated and unhappy looking (the lights are still off). Does a skunk shrimp have the strength to push a 3" plate coral?

 

Thanks,

HG

[caja]

No, they do move on their own. To be honest with you, the plate is probably coming out of the cave because it's looking for more light. They are not a low light coral and you only have 3 watts per gallon on your 12 gallon tank. Very low. They require bright light and low to moderate current.

 

You either need to get rid of that plate before it dies or upgrade your lighting.

[Hgarner]

I hear you, and the other information out there appears to confirm, but my confusion really stems from the fact that he's been happly only in the shade (and only when I have just one of the 36w bulbs installed in my hood).

[Hgarner]

I guess I just have a weird plate. I put him back in the shade, and he inflated bigger than he's ever been. I sure wish I could train him for more exposure, though, since he's hard to see in his little cave.

[Tempest]

He may not be inflating because he's happy, but rather because he's trying to maximize surface area to absorb light. Just my .02

[Hgarner]

I see your point, but it still doesn't explain why the coral completely retracts and remains skeletal any time he is exposed to the full light, which is how he's reacted since day 1. He also extends his arms fully at night, and occasionally during the day, and feeds normally when he's covered.

 

HG

[Dingo]

Retracting and looking skeletal during the day is the natural state of plate corals. In the wild, they tend to look like dead skeletons during the day, and like softballs at night, when they fully expand to move and feed. They are capable of climbing rockwork.(From Borneman's coral book)

 

They do tend to open up in captivity during the day, especially after you feed them. Mine puts out tentacles during the day, but stays mostly deflated, and puffs up at night. I was keeping it in a 10G under 96W PC lights with no adverse effects, and now under 250W Halides it is even happier.

[Spindog]

Also consider flow issues. My plate seems very sensitive and even slightly too much current appears to cause it to remain contracted more. Perhaps yours wants more light but is bothered when it is out of its cave by more exposure to current?

[Hgarner]

Thanks for the tips and info. I've put him out in the open on the sandbed in a very low flow area to see what happens. He walked himself out of the cave again yesterday when the lights were on, so I guess he wanted to be out there. I'd like to see how he reacts to the new setup, but if he doesn't do well, I've made plans for him to go into a friend's 140 gal/MH setup.

[Hgarner]

Happy to report that my idiocy re: the plate coral has ended, and that he has made an apparent full recovery. Tentacles are out night and day, and he's feeding greedily. Thanks again for all the advice.

[tonym]

Mine is very healthy, but does strange things too. It will puff up like a baseball like Dingo said and look like it's going to pop, but then deflates and extends it's tenticles. It onlt does this once in a while though.