Green Hair Algae

[Hobster]

Hi Randy,
I recently started getting some type of green algae outbreak. My Nitrates are 0 and Phosphate .05 to .1. I have never had this before and can not figure why. It may be only coincidence but I did start feeding my clams some live phytoplankton, but only once or twice a week at less than directed. I have read your articles on phosphate and was considering using some type of Iron Oxide. Could it be a Organic form of phosphate that my test kit will not detect? I run carbon, skimmer, macro algae and some lime.
I am not sure if the Iron Oxide would do any good if the phosphate reads low to begin with? Thanks for any suggestions.

[Randy Holmes-Farley]

Could it be a Organic form of phosphate that my test kit will not detect?

It could be, but even 0.05 to 0.1 ppm phosphate is enough to make algae quite happy, especially since that value is after they have feasted.

I think the iron oxide media might well be worth a try, yes. :)

[Hobster]

And I thought I was keeping it low by the test kit instructions of .2 or less:) I do tend to over feed the fish.

I will try some iron oxide. Thanks

[Randy Holmes-Farley]

This article give more details about recommended phsophate levels:

Phosphorus: Algae’s Best Friend
http://www.advancedaquarist.com/issues/sept2002/chem.htm