Red Montipora capricornis

AllSignsPointToFish · Jan 12, 2017

I have had a red Monti for about a year. Over the last year, it has more than doubled in diameter. The new growth is a brilliant red, as it should be, but the portion of the original colony is a more subdued purple-reddish color. I was worried about bleaching, but it's been this way for several months now. I even reduced lighting intensity for several weeks as a precaution, but I would've thought if it was going to bleach, it would've done it by now.

Any idea what could be going on? All water parameters are normal, and I have 300-400 ppm potassium when I last tested a week and a half ago.

Temp 76-77°F
SG 1.024
pH 7.9-8.1
NO3 1.5-2 ppm
PO4 0.04 ppm
Ca 425-440 ppm
Mg 1360-1400 ppm
dKH 9.5-10.9
Fe 0 (can't ever seem to register iron on the test no matter what I do)
I2 0.06 ppm
K 300-400 ppm

happyhourhero · Jan 12, 2017

Has the cap grown or has anything else grown in such a way that the flow to the discolored area has been decreased?

luis carreiro · Jan 12, 2017

Any pictures

AllSignsPointToFish · Jan 12, 2017

The flow might be slightly reduced by the way the cap has grown, but I wouldn't think it's significant.

AllSignsPointToFish · Jan 12, 2017

Sorry I don't have a more zoomed picture...the Monti is in the center back.

AllSignsPointToFish · Jan 12, 2017

AllSignsPointToFish · Jan 12, 2017

More pics:

AllSignsPointToFish · Jan 12, 2017

I can easily increase flow if that might help.

AllSignsPointToFish · Jan 12, 2017

I went ahead and bumped the flow up by repositioning the RW-4 I had pointed at that coral. Pretty sure that can't hurt :)

wkscott · Jan 12, 2017

Depending on the specific coral, I believe that this can be just part of nomal aging. I started a couple of frags about a year and a half ago and the older parts also darken. I don't think that flow is an issue as mine are in 2 different parts of my tank, no changes in flow or lighting and they both do this.

AllSignsPointToFish · Jan 12, 2017

wkscott said:
Depending on the specific coral, I believe that this can be just part of nomal aging. I started a couple of frags about a year and a half ago and the older parts also darken. I don't think that flow is an issue as mine are in 2 different parts of my tank, no changes in flow or lighting and they both do this.

Thanks. I changed the flow and figured that can't hurt anything, so we'll see :)