Zooxanthellea regulation or Bleaching???

luke

Member
Hello all,
I have a 10 gallon reef that has been doing fine. I had a small mishap with my salinity when my float switch made up for some water that was leeking out of a filter. I slowly reajusted my specific gravity bacj to 1.0235. I also corrected the leak so the tank has been stable. This caused an already stressed acropora to contract RTN ( fraged him into 6 or seven peices). There are two frags that did not die from this (that is good :) ). They seem to be doing fine.
The problem is this: I have three colonies of Protopalthoa (Button polyps) that have been doing quite well. They are growing like weeds. The problem is two of these colonies are looking very pale. They look bleached. Both have been doing very well in their respective spots for quite some time now. They both receive direct 175w light 11 hours a day. The other colony is doing very well, and if anything looks even better these days. (I don't think that it is a case of too much light, because I have had these colonies [or their parent colonies] for 4 years and they have been under MH light the whole time). I just noticed the bleached colonies releaseing packets of Zooxanthellea algeas from their mouths. This could suggest that they are just regulating their algeas.
How do I know if they are bleached, or if they are just regulating their symbiotic algeas? And if they are bleaching, what do I do? and what could be causeing it?
Many thanks
Luke
 
Top