Montipora Damage - Pics

zibba · #1 11/29/2007, 07:57 PM

I've been trying to ID this below using the SPS Predators thread with no avail. I just noticed it this afternoon. None of the other monti's in my tank are showing signs of damage. I thought it might have been moni eating nudibranch but from other pictures I've seen it doesn't appear to be the same. Seems to be the only logical thing though.

I don't have my good camera so these pictures will have to do for now. What are your thoughts? This piece has been in my tank for over 2 months without any other signs of damage. Again, none of the other corals have this happening to them. Only recent addition to my tank was some acan's last weekend.

FWIW - I could easily frag around this and remove the damaged part. The top looks normal; polyps are extended, color is fine.

dvanacker · #2 11/29/2007, 08:17 PM

It's normal....the underside is prone to die off from lack of light.

zibba · #3 11/29/2007, 09:35 PM

sweet. glad I don't have to fight off another pest. I wonder why it is only this particular coral that is having die off on the underside. I have much larger colonies that don't have die off underneath.

Should I expect this die off to spread much? Is there anyway to prevent the spreading?

kynan · #4 11/29/2007, 10:17 PM

keep an eye out for nudi's...dead spots on top; get out a flashlight after the lights are out for a while and make sure there's no nudi's on the edges undeneath.

Crazysps · #5 11/29/2007, 10:36 PM

How close is that anemone to that monti, that things is huge and it would burn that monti in a second.

zibba · #6 11/29/2007, 11:22 PM

The nem is far enough away currently to not have caused the damage. It is big though. Thanks for noticing!

zibba · #7 11/29/2007, 11:23 PM

Quote:

Originally posted by kynan
keep an eye out for nudi's...dead spots on top; get out a flashlight after the lights are out for a while and make sure there's no nudi's on the edges undeneath.

I'll keep a look out. Hopefully it is just a dead spot from lack of light that I have failed to notice.

miwoodar · #8 11/30/2007, 01:30 PM

Some areas of mine have died off underneath too. For me, it has always begun in the area that receives the least flow.

Jester · #9 11/30/2007, 01:51 PM

I have had similar thing happen too... my caps with turn to a darker more stone like color and actually grow a little algea on the bottom... but the top keeps growing out and expanding...

Bender · #10 11/30/2007, 09:41 PM

Could it be possible that there was an air bubble there that caused that spot to die off?

zibba · #11 11/30/2007, 09:49 PM

Quote:

Originally posted by Bender
Could it be possible that there was an air bubble there that caused that spot to die off?

A member of our local club wondered the same thing. I can't say that I've ever seen air bubbles get trapped under there until now. It's interesting though because the other caps right next to it are getting similar amounts of flow and not experiencing any damage. Could be just the shape of that cap caused some smaller bubbles to get trapped resulting in the dead spot.

I tried looking for moni nudibranchs last night and didn't see anything. General consensus seems to be that, that is not the cause (which is definitely a good thing).

Bender, have you experienced this with you plating corals before?

LockeOak · #12 11/30/2007, 11:49 PM

Possible explanation: In the center of the cap it's probably pretty thick, so the skeleton in the center of the thickest spot may be completely dead... i.e. the living polyps on the top surface have no connection to the (formerly) living polyps on the underside. Without any light they eventually die off underneath, starting from the darkest/thickest spot, the center.

Jester · #13 12/01/2007, 02:08 PM

I've never noticed polyps on the bottom of my Monti Caps... The air bubble is a good idea, I would have never thought about that as being a possibility...

eskymick · #14 12/01/2007, 03:22 PM

I might suggest that you watch your alk levels closely, too. I've noticed that some of my sps corals begin to bleach in the "shaded" areas when my alk stats to approach the low end of acceptable paramaters.

I solved that problem by installing a two-part dosing pump.

zibba · #15 12/01/2007, 03:25 PM

I dose two-part as well, but I do it manually. Yesterday when I checked my levels, my alk was at 9 dkh. Normally, I keep this around 10-11, so it had dropped a bit. I'll continue to watch it closely though. Thanks for the heads up.

Doesn't appear that the "spot" has spread at all over the last few days since I originally posted. I'll be sure to update if there is more deterioration.