Acro turning brown

[Jdadams]

I have various types of acroporas and they all seem to be coloring up nice since I have gotten then from the store. But I have one green millepora frags that was really green for about 2 months and is starting to turn brown. Why are all of my other acro's coloring up and the green milli turning brown?

 

[Jdadams]

It is a 56gal. Cube and I have 3 other kinds of millepora, blue steel stag acro, another type of stag that I don't know the name of, Tri color valida acro, green stylophora, pink birdsnest, yellow scroll coral, 8" sebea anemone, candy coral, frogspawn and brain coral. I have a 150w 14k metal halide light, and 3 hydor koralia pumps they are the 4 or 5 size so I have excellent current throughout the tank.

 

[Jdadams]

My tank is 25" high and my liverock comes up about 15 to 20 inches and all of my sps corals and my maxima clam are on top and my lps corals toward the bottum and in the sand I have my sebae anemone. My lights are left on for about 9 hours a day.

 

[Jdadams]

Params are good. Kh is about 10. Calcium is about 460. And nitrate and phosphate don't show up. It is right on top with all my other milli's.

 

[rolo65]

Depending on the type of Millie it is possible it's getting to much light....try moving it down a few inches or so but still try to maintain good intermittent flow

 

[snowmansnow]

correct me if im wrong, but might that mean thats the coral is allowing an increased population of zooxanthella(spelling but you get the picture)?

It's when they bleach that you have to be really concerned.

b

 

[cr500_af]

SnowManSnow;574605 wrote: correct me if im wrong, but might that mean thats the coral is allowing an increased population of zooxanthella(spelling but you get the picture)?

It's when they bleach that you have to be really concerned.

b

And too much light typically causes bleaching, not browning.

 

[snowmansnow]

that's what I was thinking too.... reason being the coral allows more algae in order to supplement its food source (photosynthesis)...

again, correct me if I'm wrong I don't wanna guide someone the wrong way.

B

 

[cr500_af]

I think you are exactly right... from what I understand that's why we do a slow acclimation to stronger light (to let the zooxanthellae increase in number slowly).

 

[jef4y]

But if that were the case, over time it should balance itself out and go from brown back to whatever color is native right?

 

[cr500_af]

JeF4y;574623 wrote: But if that were the case, over time it should balance itself out and go from brown back to whatever color is native right?

Usually (again, from what I understand)... though I can say it is not 100% due to the fact that I've had some acros stay brown eternally until they get the light they want... so it is safe to say that there is a certain threshold of light under which the color won't ever be there. On the other side of the coin, too much light too soon may bleach so badly that they never recover (I assume the light shock is killing the zooxanthellae).

 

[jef4y]

That sounds logical to me.

 

[ralph atl]

IMHO, it's not too much light. Those 150 watters won't do that...if anything it's not enough. However, I've found that too much phosphates will cause corals too brown (also not enough light) and you would need a test kit that measures low range phosphate like the new Elos, Hach, DD Merck, and colormeter.