Coraline turning white?

[Sea Wizard]

My 125g tank is approx. 2 yrs old. At the first of the year I lost every thing to an outbreak of cyano that would not die. Only life that survived was a few hermit crabs, some snails, and a few hairy mushrooms. Wife and I sucked it up and cleaned the tank, rock, and proceeded to redo everything. I was very surprised at the pods that were still alive, any hoo the tank is looking better and looking up. Problem being is that the coraline is turning white. I have some very dark purple, pink, and a red looking coraline(tried to scrub the red off thinking it was cyano). It seems to get a white edge and what looks like flakes all over it. Was using PurpleUp and the coraline took off and was looking great, now not so good. Specs are 0 phospate, 0 ammonia, 0 nitrite, 5 nitrate, 1.0235 salinity, 460 calcium.
Tank houses 2 rics(1 orange, 1 green, 1 3" toadstool, 1 3" goniapora, 9 quarter size hairy mushrooms, 1 Featherduster, sand sifting star, doz blue leg hermits, 6 astrea snails, coral beauty, and a common damsel. Can someone help me out with this?

 

[Dave3112]

My guess would be that your Magnesium is low. If you have a test kit for that I would check it. It should be around 1350-1450 i believe.

 

[zking1987]

from what I have experienced, when calcium gets low coraline starts to turn white. maybe double check that. did you have coraline out of water for a decent amount of time?

 

[Troylee]

have you changed your bulbs recently???

 

[subielover]

What is your tank's alkalinity and magnesium?

 

[clowns101]

Depending on how long it is exposed to the air,it will turn white,mine will turn white often times when I will clean somthing in saltwater and let it air dry for 1-2 hours,like my Powerheads.

I wouldnt worry,it could be unstable tank also,thats just my experince.

 

[subielover]

When alkalinity and calcium are jumping around on you, coralline has a tendency to go white (die-off.) I wouldn't use purple-up, just monitor Ca., Alk. and Mg. and dose 2 part when necessary.

 

[clowns101]

Oh exusse me,I thought you were asking in general what alk and mag were for your self,please forgive me for that mistake,I read it as like you were asking for the information,I will go back and edit my post and fix that.

Once again,please forgive me for that error.

 

[Troylee]

Only time I had that problem is when I changed bulbs it bleached out... That's why I asked about bulbs but params are just important...

 

[ddiver]

check your Strontium level also...corraline tends to bleach when levels are low...should be around 8-10ppm.

 

[subielover]

Oh exusse me,I thought you were asking in general what alk and mag were for your self,please forgive me for that mistake,I read it as like you were asking for the information,I will go back and edit my post and fix that.

Once again,please forgive me for that error.

No worries, I was a little confused as well.

 

[Sea Wizard]

The parms are listed in the 1st post. Don't know about mag as I don't have a test kit. Alk is 10dkh, everything seems to be stable. I am using RO/DI water to topoff. RO system is new, only about 40 gal ran through it. I have not changed my lights, running 8 54w T5ho, with 4 65w PC as a supplement, although bulbs are due to be changed out (have a 250w MH, but not installed) . Before the outbreak of cyano system was truely excellent, now the few corals I do have appear to be thriving, they are opening great, stretching out, just having a bit of a problem with the coraline bleaching out. Should I return to using Purple Up to try and kick start the growth again? Had fantastic results when I was using it. Or should I dose with kalkwasser(I will use Mrs Wages Lime)? Really is bugging the heck out of me, I really do appreciate the help and any advise.
Rechecked the calcium level is 480ppm. Although ph is low now running 8.0.

 

[Suppressivefire]

Oh exusse me,I thought you were asking in general what alk and mag were for your self,please forgive me for that mistake,I read it as like you were asking for the information.

Lol I thought the same thing. And my guess is unstable parameters or could very well be that the air just got to it.