Acro problem

[sorcerer]

I'm having a problem with an Acropora Colony I've had for about 6 months now. The problem started about three days ago. I noticed that a couple of the branches were not polyped out as usual and on closer inspection I found that they were now white skeletons with no tissue on them at all. The next day a couple more were the same way and last night I found that two more had gone the same.

Two questions: Any ideas on what is causing this and what I might do to stop it. Second, there are two comensal crabs in this colony, if the colony dies is there any way to get them to move to another colony without oving the problems as well?

here are my params as of yesterday:

SG - 1.025
Temp - 80
pH - 8.3
ammonia - 0
nitrite - 0
nitrate - 0

alk - 9dKH
calc - 475

ANy suggestions would be appreciated,
TIA

[mwrager]

How old is your lighting and when did you last do a water change?

[EdgeKrusher]

Did the bleaching start from the tip of the branch or from the middle of the branch? Did you notice anything out of place anywhere on the colony prior to the bleaching of the branch? Many things could have cause this bleaching... Stress, a disease, lighting, water quality etc.

EK

[sorcerer]

mwranger - all of the bulbs are 6 months old and the last water change was last weekend, 20% as I was finishing up my battle with hair algae.

edge - it is hard to say where the bleaching in starting from, the branches are fine when the lights go out at night and when they come on again the next day the branch is gone like the others. No signs of stress in the tank as all my other corals and critters are doing fine, water quality is measuring fine, I haven't seen anything bothering the colony or out of place near it, there aren't any other corals close by, disease may be the culprit.

[mojoreef]

Walt discribe the crabs in the colony

Mike

[sorcerer]

One is a little smaller than a dime, flat body, arange coloration with a goldish red and white stripe around its body. It has very small legs and the large claws are fairly smooth with little to no seration. The body and legs are very flattened and not much thicker than a dime.

The other is about half the size and is a deep reddish black with a gold stripe around his body.

Both crabs were in the colony when it was purchased. I have seen them clean algae, run off snails, and generally live very peacefully with the colony.

[mojoreef]

Walt the reason I asked is thier is a fuzzy form of an acro crab, usually dull white or dull red with what looks like a light fuzzy coating on its shell and claws. re reading your post it sounds like an rtn event. This is a tough one to beat, but here is a little trick I have done on the past. Break off the affected braches (even if its just starting on the branch). Get some crasy glue and coat the bare skeliton and make sure you come a little bit onto the good tissue. This should contain the spread of the rtn/bacterial infection. Usually the tissue grows right back over the glue.

good luck my friend

Mike

[sorcerer]

Netiher of these crabs is fuzzy unless it is so fine that I can't see it (considering my eyesight that is still possible...LOL) I'll give your recommendation a try, Thanks Mike.

[mojoreef]

Walt if it was a fuzzy you would see it. The glue trick is a bit unconventional but has worked many times for me and others. It tends to kill any bacterial populations in the immediate area with out hurting the coral itself.

I hope it works for ya, let me know


Mike

[VINA DEL MAR]

Sorcerer your problem could be temperature related.If your acro shows more bleaching in the morning and if you tank has a temperature alarm look and check it ,what was the lowers it got at night when the lights were off?Having strong lighting on your tank like I do could create a big fluctuation on temperatures.You only mentioned the tank temp during daytime.When I had a case of bleachig my temperature in my tank was 81 in the day(not having a chiller)and at night was 78!.Some corals are more sensitive than others it depends the depth of where these colonies were taken.Your tank params are excellent I can't think of anything else.Have you checked your heaters lately?Is it the right size for the tank?
VINA.

[SunnyX]

Post a pic so we can better ID whats going on.

[sorcerer]

Vina,
After moving to MH lighting I did quite a bit of work on maintaining a constant temp, Generally, barring power failures, my tank stays between 80 and 80.5 during the night and day both. I tend to check my heaters on a weekly basis when everything is working as it should just because I had a failure early on and have gotten a little paranoid about them. But for the entire time this colony has been in the tank the temp has been consistant at 80 to 80.5.

I did double check this this weekend when I first noticed the problem.

[VINA DEL MAR]

Sorcerer can you also check your Iodine in your tank?Sometimes it could be low.If you can take the colony out and dip it in some tank water with a ratio of 1 drop of Iodine to 1 gl of tank water for ten minutes to disinfect the colony it could help.Add some to the tank if is low(iodine)today.VINA

[sorcerer]

Vina,
Much as I hate the iodine test, I do have one, I will check it tonight and see what the level is.
thanks

[VINA DEL MAR]

Let us know what the readings are!
VINA