Blastomussa Going White?

[cuticom]

I'm having problems with my Blastomussa, some of the plyps, in almost random places are going pale. Theres no sign of rotting or anything. The dark brown rims just suddenly get a white haze over them, and now more and more polyps are getting it. The pokyps with the haze also stay closed, though not totally closed.

I just checked it tonight in the dark, and it has some sort of creature in it, I think maybe a bristlstar? what ever it is theirs at least 12 of the tentacles, they are kind of wavy and seem to be striped red and white, their quite small though. Theres also some strange little brown and orange polyp, but I've never once seen it move, a purple nobbly coral that has never seemed to move anywhere near the blasto but is on the same rock, an encrusting coral that has blasto growing under and around it and I 'think' thats it.

The blasto is under 40w flourescents but is also getting 4 hours a day of 100w MH lighting, the tank is 60cm deep. Is it getting too little lighting? too much?

Oh and I got it cheap as it had a dead patch which appeared to be a coral sting. The patch was long dead and the blasto around it was completely healthy, it had also been at the store for three weeks already so I wasn't worried about infection....

Please some help? this is only my second coral and I don't wanna lose it!

 

[SkiFletch]

Really hard to say without a pic

 

[Colin_T]

As SkiFletch said, it's hard without a pic. However, if the coral is losing colour it could be bleaching, (losing its symbiotic algae) or it could be dieing. Bleaching occurs when the conditions are not good and the coral is stressed. The coral looks normal but goes white very quickly, usually overnight.
If the coral is dieing it will go white but often goes fluffy or falls over and wilts.
It could be getting attacked by another coral in the tank or a predator like a nudibranch or snail.

 

[cuticom]

I;ve tried taking pics but they can't pick up on the slight colour change...

The only other coral in the tank is a sun coral which is two feet away. There are corals on the rock but since the blasto is growing around and in some cases under them I'm guessing they pose no threat.

What does a blasto look like when polyps are fully closed? any pics? I haven't actually seen this coral with all it's polyps closed and I was thinking that maybe the pale polyps are closed? Does it change colour when it closes?

It's definitely not an overnight change, it's been really gradual since I got it, I got the coral a week ago.

 

[Colin_T]

Try turning the tank lights out and using the flash when photographing the coral.

If there are only 2 corals in the tank and they aren't near each other then they won't be fighting.

Blastomussa has a tubular coral skeleton and when the polyps retract there is a tangled mass of tubes. When the polyps retract they won't be visible and don't change colour.

Try increasing the lighting period from the metal halide by an hour. Increase it an hour each week for a couple of weeks and see if that helps. Alternatively, move the coral higher up in the tank so it is closer to the light.

 

[cuticom]

Oops should have mentioned I am slowly increasing the halide it came from poor lighting at the store though, the coral tanks only have a halide each and the blasto was well well away from it whereas it's directly below the halide in my tank.

I think it may be the polyps retracting I see, as they were all fully out when I checked this morning, no pale ones at all, but when I checked a few minutes ago a small patch had gone pale.

I know it doesn't retract fully, when I moved it to the tank the polyps were still kinda sorta open.

 

[Colin_T]

That could be part of the problem. If the coral isn't fully retracted before packing and during transit, the polyps can be damaged and bacteria or fungus could be infecting it.
I always make the shop assistant wave their hand around and above the coral to get it to fully retract inside the skeleton before I allow them to bag it up. And I don't let them wrap it in newspaper either. In fact if I am going coral shopping I quite often take buckets with me and get the corals put straight into the buckets.

It could also be it is stressed from the halides. If it came from low light the halides might be too much for it, even tho they are only on for 4 hours a day.

 

[cuticom]

Coral was transported upright in a styrofoam box and completely covered in water, it is MASSIVE and it's on a good 2kg of rock, so it was pretty stable and it was fine during transport, the coral didn't roll around or hit the sides at all. It wasn't packed in Newspaper either.

Should I just leave the halides and see if it that changes it at all? as I was going to take it to 5 hours a day...

 

[Colin_T]

Yeah maybe leave the lighting for a week and then increase it by one hour. The coral should be able to acclimatise to the halides by that time.