Bleached ZOOS?

[Whitebird1]

Treating a frag that was totally closed up, 2 polyps, white, basically melting away.
During dips I rubbed off what seemed to be a dead layer of outer skin and they started to open. Still no color. Now I checked and 4 new polyps have grown. Should be dead?
Anyone see this before?
GregH

 

[john90009]

were they newly acquired zoos? Also if there under the t-5 keep them as low as possible to see if they will get back color- if i put any of my zoas off the ground they will close up or change colors.

 

[naso150]

Ive seen mushrooms look that way after drifting under rock or to the back of the reef for long periods with out light. Have they been on your rack for an extended period? They usually recover with slow acclimation up to higher light areas. This could also be from to much light in which case the coral will expell most of its zooanthelae to try and lower the O2 level within its tissue. HTH

 

[Whitebird1]

No details known but I can assume that the lights were med and never in the shade, possible shipping or acclamation trauma. naso150, my guess too. need a treatment?

Coral bleaching occurs when zooxanthellae densities within coral tissue become low or the concentration of photosynthetic pigments within each zooxanthella decline. Color loss also comes from reduced concentrations of Green Fluorescent Proteins (GFP) from the cellular pigments of the cnidarian itself. The result is a ghostly white calcareous skeleton. The coral then die unless conditions improve enough to allow the zooxanthellae to return.

Zooxanthellae directly or indirectly experience the stress that their containing corals undergo. Exposure to air during low tides and damage from solar radiation in shallow water environments are two of the ecological stressors coral and zooxanthellae face. Temperature changes now provide the most stress to the zooxanthellae-coral relationship. A 1-2 degree Celsius temperature rise for 5–10 weeks and a 3-5 degree decline for 5–10 days have produced a coral bleaching event. Such temperature changes induce cell adhesion dysfunction which detaches zooxanthellae from their cnidarian endodermal cells.

 

[onefish2fish]

ive heard of people bleaching their zoos on purpose to make new colors

 

[naso150]

I would try starting them at about 1/4 the way up from the bottom of the tank for a week or two. Then half way up for a week or two. If the colors begin to come back then continue upwards. You want to give them a chance to slowly build their zooanthelae back up. If it gets worse then you know you either went too high too fast or the original problem was from too much light. Then I would try them right on the bottom for a while.

 

[ds4x4]

heard of palys doing this and regaining their color. i would say if they are healthy enough to sprout some new polyps they should recover fully

 

[Scottyrock]

greg
when my tank had that crash that you helped me with, my zoa also had a layer of skin come off during the rub down in the bath..... they didnt bleach though

 

[Mbodell]

Some of my mushrooms have done this as well. Color always came back.