Acro bleaching question

[trilinearmipmap]

I have a purple Acro, in the past 9 months or so it has grown nicely from a 2" frag to several inches across. A couple of days ago I moved a powerhead, and inadvertently one branch of the Acro was being blasted full force by a Tunze 6105 Stream from about 3" away.

Yesterday I noticed the tip of that branch was bleaching so I moved the powerhead away from the coral. Today about the last 3/4" of that branch is bleached, the rest of the Acro looks fine. All routine water parameters (temp, Alk, Ca, Mg) are within normal limits, nitrate is zero to 0.5 and all the other corals are fine.

My question is, will the bleaching spread to the rest of the Acro and should I trim off the bleached branch to prevent it spreading? Obviously mechanical trauma started the bleaching problem but if there is some kind of infection setting in on the damaged part of the coral then would removing that branch help?

[lorenz0]

are you sure its bleached or rtn'ing. I did the same thing when I first got into SPS and even after moving the powerhead it eventually rtn'd on me

[Myka]

I would guess there is tissue recession (different than RTN and STN) from the damaging effect of blasting the coral. I would watch very closely, and if the recession doesn't stop I would clip that branch off at least 1/2" from the edge of the bad tissue.

[ScubaSteve]

Originally Posted by Myka

I would guess there is tissue recession (different than RTN and STN) from the damaging effect of blasting the coral. I would watch very closely, and if the recession doesn't stop I would clip that branch off at least 1/2" from the edge of the bad tissue.

+1 on trimming it if it looks like it's about to go off. Lots of SPS can just go POOF! like someone lighting a fuse once tissue recession starts. Watch it and if it looks to be stable, leave it and hope it will recover. Otherwise, trim the bugger. I'd still recommend breaking off the dead area to encourage the growth of a new axial corallite and branch. Make sure you keep the cut area clean of algae so it can grow back.

I made the mistake a while back of not fragging a colony when it started to receded. Not only did I end up losing 3/4 the colony by the time I finally did frag it to save the living pieces, it also triggered recession in neighbouring colonies. As soon and I got rid of the dying parts in the big colony everything else in the tank was happy and healthy again.

[Myka]

Originally Posted by ScubaSteve

I'd still recommend breaking off the dead area to encourage the growth of a new axial corallite and branch. Make sure you keep the cut area clean of algae so it can grow back.

Good call.

[trilinearmipmap]

OK thanks for the advice.

My plan is to remove the whole branch and attach it as a frag somewhere else on the rock, if the branch survives then great.

[untamed]

Originally Posted by ScubaSteve

+1 on trimming it if it looks like it's about to go off. Lots of SPS can just go POOF! like someone lighting a fuse once tissue recession starts. Watch it and if it looks to be stable, leave it and hope it will recover. Otherwise, trim the bugger. I'd still recommend breaking off the dead area to encourage the growth of a new axial corallite and branch. Make sure you keep the cut area clean of algae so it can grow back.

I made the mistake a while back of not fragging a colony when it started to receded. Not only did I end up losing 3/4 the colony by the time I finally did frag it to save the living pieces, it also triggered recession in neighbouring colonies. As soon and I got rid of the dying parts in the big colony everything else in the tank was happy and healthy again.

I think this is excellent advice and is identical to experiences that I have had. I also would support the suggestion of "snapping" the dead end off, rather than "cutting/trimming". Sometimes the "snap" doesn't happen where you would like, but a snapped end regrows a new growth tip, while a trimmed end doesn't do it as quickly...and sometimes never.

[Myka]

Originally Posted by trilinearmipmap

My plan is to remove the whole branch and attach it as a frag somewhere else on the rock, if the branch survives then great.

I would suggest you just toss that piece in the garbage. You never know for sure what the problem is, so why risk one little frag for your whole tank? I remove anything questionable from my reef. My reef is worth too much (and I'm not just talking money) to risk a little frag over.