Selective bleaching of Montiporas?

Phantom Phish · 10-07-2003, 06:40 PM

After doing great for months, all of my Montiporas have suddenly started bleaching. I have several color varieites of M. digitata, and what was turning out to be a real nice orange-red M. capricornis. I started noticing all of them beginning to bleach yesterday, and today it has gotten worse. My other sps's are doing fine (for now), including several Acropora sp. LPSs and the two softies I have (Sarcophyton elegans and a large colt), also seem to be doing fine.

The only thing that I've done recently, is that for the last several days I've been dosing some Kents Tech M magnesium. I've been wanting to bump my calcium up a little, after having some difficulty keeping it where I want it. I checked my magnesium levels (Salifert test kit) and indeed they were low at 1200-1230 ppm.

Could the magnesium be causing my bleaching, or is that just coincidental? I can't find anything else wrong with my water parameters.

laddy00 · 10-07-2003, 08:18 PM

I would try to do some water changes to see if something is out of whack. Did you try to raise the magnesium quickly?

Geoff · 10-07-2003, 09:37 PM

i have seen this on mine M. caps. i have found it is usually due to something falling on that area. maybe some salt creep came loose and fell on it. sometimes a little detritus will collect and when i blow it away there is a small bleach spot. it usually heals really quickly and i can not even see where it was after a few days. i do not see any differences in the growth patter for the area either. do not have any M. digita, but would think it would be similar.

G~

Phantom Phish · 10-07-2003, 10:12 PM

I think it has to be something systemic. All of the Montiporas (5 of them, 4 digitata and 1 cap) started bleaching at the same time. The Mg level raised about 50 ppm the first day, then its only come up another 30-40 ppm over the last 3-4 days. This morning the Mg was at 1290 ppm (have been stuck there the last 2 days). Don't know why its not coming up any more, but i'm going to stop dosing Mg. I just hope its not some kind of pathogen specific to Montiporas. Don't even know if such a beast exists.

gregt · 10-08-2003, 05:06 AM

In the Tampa area we had a plague of Monitpora eating nudibranchs. Nearly everyone in the area got it and lost all their M. caps, and many M. digi's as well..... Might not be the same thing, but it's possible.

Phantom Phish · 10-08-2003, 07:59 AM

Yeah, I'm worried about something like that too. But its not a localized process, like I might think a nudibranch would be. It looks like diffuse bleaching involving the entire coral/frag. Some Montiporas are more bleached than others, but they are all affected to some degree. The thing that gets me is that my acros still look fine, and I thought they were supposed to be more sensitive/less hardy than Montiporas.