Yellow Coral getting a green hue to them?

[Charterreefer]

Hi Randy,
I searched the web and couldn't get a definitive answer (or even something close) so I thought I would drop by with this question. What could cause all 5 of my yellow acropora corals to develop this green hue in them? FYI: I had a Triton test done two months ago and have since used their suggested chemicals in the doses given. The only parameter out of speck should be the higher Chromium level they found. I have three 80 watt Actinic, one 80 w Coral+ and two 250 watt radiums lighting the tank.

 

[bif24701]

Hi Randy,
I searched the web and couldn't get a definitive answer (or even something close) so I thought I would drop by with this question. What could cause all 5 of my yellow acropora corals to develop this green hue in them? FYI: I had a Triton test done two months ago and have since used their suggested chemicals in the doses given. The only parameter out of speck should be the higher Chromium level they found. I have three 80 watt Actinic, one 80 w Coral+ and two 250 watt radiums lighting the tank.

Here is your answer:

Yellow
Highly dependent on Nitrate and PO4 levels. Of course all SPS colors are highly dependent on lack of N and P so I wanted to start with probably the easiest color to get, yellow.

https://reefbuilders.com/2008/09/03/guide-of-sps-coral-coloration-make-them-more-vivid-bright/



What is your NO3 and PO4? This is what drives the yellows according to the article, not macro/micro elements.

 

[Charterreefer]

My NO3 is 1-2ppm. PO4 is unreadable because of a small amount of cyano growth. It is low being that I had to stop the GFO because the sps started to become pale. Since removing it colors are coming back.

 

[BlueCursor]

Iron will also turn yellow corals green. If you aren't dosing anything with iron, then that isn't the issue.

I think NO3 of 2 would cause a green hue. I don't know if 1 ppm would.

 

[Charterreefer]

Iron will also turn yellow corals green. If you aren't dosing anything with iron, then that isn't the issue.

I think NO3 of 2 would cause a green hue. I don't know if 1 ppm would.

Sounds like there is a very fine line between starving your corals (which I was doing until recently when I took GFO offline) and providing the sps with enough to grow! My recent Triton test results actually said to feed more lol.
Then you have the "Masters" tanks -- see Mike Paletta's recent article series, were the pro's tanks run high NO3 as well as PO4 and everything looks just fine!???