Don't know what they were, but they're dead now

[rbird]

Please help me find out what happened to this colony.



I have no idea what they were. I thought maybe some kind of tube anemone. The entire colony was alive last week and looked like the the four remaining tubes on the right side of the picture. They were brown tubes with anemone like tenticles. Now they look bleached white and purple. They had been growing from a piece of live rock that has been in the tank for about 4 years.

The tank is 120 gallons

Water paramaters are as follows:

SG 1.022
Ca 400
pH 8.2
Alk 3.0 meq/L
Temp 79
Nitrate 0
Phosphate 0.1

Lighting: 2 250 watt 10K mh and 2 55 watt actinic pc's. Mh bulbs were replaced about 2 months ago.

Everything in the tank has been stable. I have been struggling with aiptasia and a red algae. You can see the algae on the rock.

I dose B-Ionic for calcium and missed a few days over the weekend. My calcium is typically closer to 420.

I usually do a 10 gallon water change every weekend, but missed this weekend. I use a 4 stage ro/di filter and the filters were replaced about 2 months ago.

Recent changes

I started using Seachem phosphate remover and carbon about a month ago to try to get my phospate level down and control the algae.

I moved some of the live rock around to improve the aquascaping about a week ago.

I tinkered with my Koralia powerheads last week after reading discussions on reef central by removing the cones to see the effect on flow. The result was too much turbulance that disturbed my sand bed so I replaced the cones.

Everthing else in the tank is fine.

I would appreciate any help in both identifying this animal and finding out what went wrong. These things must have been pretty hardy, they survived a week long black out during the 2004 hurricane season that wiped out most of rest of the tank.

[ACBlinky]

When you moved the rockwork, did it change the amount of light these animals are receiving? They may have bleached because they're suddenly being exposed to much more or less light than they're used to; if this is the case, they may recover, especially if you can return them to their former light level.

I don't know what they are, it's possible they're an anemone, a type of coral, I hope someone can ID them for you. Can you get a more detailed close-up of them?

[AquaReeferMan]

Looks like a sun coral.
http://www.melevsreef.com/suncoral.html

If is was that, they prefer being in the shade. They are a non photosynthetic group of polyps.

[rbird]

Here are a few more pictures. I had trouble getting a better closeup shot in focus. Santa didn't bring me a new digital camera.

First, the survivors








I didn't move the rock they are attached too, so I don't think they are getting any more or less light than they have been for the past several years.

Everything else in the tank is doing fine. It really has me perplexed how these could get bleached like this in less than a week.

[Frick-n-Frags]

you could spot feed those. I think they are a non-reefbuilding stoney coral and I'm pretty sure non-photosynthetic. I still have the one that came with a piece of LR back in maybe 1992. it lives in my sump, right where the overflow water comes in (alligator sponges are there too). when I have to kill the main pump, i try to spot feed it.

[johndonaldson3]

first survivor picture is cup coral. The colony that is dead looks like a type of slow growing brown color coral that you get on a lot of rock for the Gulf of Mexico, like rock from Tampa bay Rock.

[greenbean36191]

It's Cladocora, which as frick said is a non-reef building stony coral. IIRC it's facultatively zooxanthellate, so can be found with or without zooxanthellae.

There are three things that jump out to me about your situation. Your salinity is low. It should be about 1.025, though I don't think that did the coral in so quickly. Also, the change in lighting might have caused bleaching, which is recoverable, but from the pictures it looks like the coral really is dead. The big thing though is the algae. Notice that it's all around the dead coral, but not near the live one. Corals and algae don't get along. A lot of people worry about chemical warfare from other corals, but they don't even think about it happening between other organisms, which it does. Red and brown algae are particularly nasty, especially if they get damaged.

[rbird]

I've never done anything to try to care for them. I just thought it was something cool that started growing out of a piece of live rock after several years in the tank. They grew despite my poor husbandry after the tank was decimated in 2004. It wasn't until this year that my interest in the tank was reinvigorated.

If they do like low light then replacing my mh bulbs might have been the cause. The old bulbs were about 2 years old. But the bulbs were changed at the beginning of November and the tubes looked ok up until I left for a few days during Christmas.

I will try to spot feed them tonight when my lights turn off. I think I may also have a shadier spot to move them to.

Do you think there is any chance that the bleached tubes are still alive?

[rbird]

The images I found of Cladocora look exactly like what is in my tank. I think that might be the correct ID.

The algae has started to recede since I started attacking my phosphate levels. I'm hoping to have it under control soon. By the way, I think I may have gotten a bad batch of IO salt. Has anyone else noticed elevated phospahate levels using this salt.
Before I started using phosgard I tested my ro/di water, freshly mixed salt water, and tank water. The fresh water was clean, The freshly mixed salt water measured 0.2 and the tank water measured 0.1.