Pale? Grey? Tan? Or okay?

[Brandon McHenry]

The fact that this coral became paler/faded as well even though it shows good growth indicates to me that iron is a likely candidate. I saw the same when I stopped using GFO because my PO4 would got to 0 and stay stable without it, I saw my toxic green Acropora humilis get paler as well. This quickly reversed once I started dosing iron.

That’s interesting. I’ll have to do some research on iron and means of reliably testing for it. @Randy Holmes-Farley if you have any helpful info on this I’d love to hear your thoughts!

 

[Graffiti Spot]

I am just curious how iron affects the green coloration of acropora. I have seen a few references to using it before.