Coraline Algae dying off

[horseplay]

Have you seen this before? Water parameter is good and corals are doing good. Started from the center then spreading for about 5 days now. At the spreading edge there is some mucus.

 

[saltkreep88]

Have you tested mag recently? Also, any changes to the intensity of your lights?

 

[horseplay]

Mag is 1100. Have not tested for a long time. So it's low. Used to get 1500+. But I doubt it's the reason. Spreading out from one point like a virus. Coraline on the rocks is ok.

 

[redfishbluefish]

Although your mag level is low, I would agree it's not the mag. A mag of 1100 gives you an "available" calcium level of 367, and that's still just fine for laying down new carbonate structure.


You mentioned mag levels, but what's going on with you alk and calc number?

 

[horseplay]

Alk has been in the 7.1 to 7.7 range. I have been increasing the dosage. I dose similar amount of calc (a little less) as Alk. The few times I check calc was about 400. I check Alk almost daily. I have not add any new coral to the tank for at least 1 month now.

I wonder if it would eventually spread to the whole back wall. Or even the rocks. The overflow and back is separated by silicone.

 

[horseplay]

Although your mag level is low, I would agree it's not the mag. A mag of 1100 gives you an "available" calcium level of 367, and that's still just fine for laying down new carbonate structure.

Paul - where can I find this mag/ca relationship? This makes it important to check mg levels as we try to maintain ca level @ ~420 ppm.

 

[jgraz]

Here is some good reading on it. This same author has more then a few articles on all three of these additives. All are excellent reading.
http://reefkeeping.com/issues/2006-06/rhf/index.php

 

[redfishbluefish]

Paul - where can I find this mag/ca relationship? This makes it important to check mg levels as we try to maintain ca level @ ~420 ppm.

Not sure if it was a "Randy" article or not, but I read that incorporation of calcium is in a direct proportion of 3:1 for magnesium (ppm). If mag was too low, the only "available" calcium was 1/3 magnesium. I'll see if I can find the article and get back to you.



EDIT TO ADD:


THIS is not the actual article I originally read, but does talk about the 3 to 1 ratio of magnesium.