Bought a used 13.5 gallon tank, Macroalgea are turning white

[rbloom]

I bought a used tank and brought it, and all of the inhabitants, home last week (July 4th). Everything has been going well. The anemone and coral appear to be thriving, and the clownfish has calmed down and isn't pacing anymore. But, yesterday morning I came downstairs and the macroalgea was turning white. Last night I did a 10% water change and removed most of the parts that had turned white. This morning it looks more transparent. The LFS told me that this is new growth, but it isn't. I have some hair algea that has formed over the last week.

Is this something to worry about or just let it alone and it will fix itself? I am experimenting with a timer on the tank light (starting today), and the tank is by a window, so it is probably getting more light than it should.

Tank info:
ph - 8.0-8.2
Amonnia - 0 ppm
Nitrite (NO2) - 0 ppm
Nitrate (NO3) - 0 ppm

 

[Dan_P]

I bought a used tank and brought it, and all of the inhabitants, home last week (July 4th). Everything has been going well. The anemone and coral appear to be thriving, and the clownfish has calmed down and isn't pacing anymore. But, yesterday morning I came downstairs and the macroalgea was turning white. Last night I did a 10% water change and removed most of the parts that had turned white. This morning it looks more transparent. The LFS told me that this is new growth, but it isn't. I have some hair algea that has formed over the last week.

Is this something to worry about or just let it alone and it will fix itself? I am experimenting with a timer on the tank light (starting today), and the tank is by a window, so it is probably getting more light than it should.

Tank info:
ph - 8.0-8.2
Amonnia - 0 ppm
Nitrite (NO2) - 0 ppm
Nitrate (NO3) - 0 ppm

Two thoughts.

Plants need nitrogen and phosphorous. Your levels are likely too low for maintaining algae.

The plant turning white could be sexually reproducing. The white parts are empty now and will decay away.

 

[paragrouper]

I use chaeto grow for both my refugium and the Halimeda in my display. It is essentially fertilizer for macro algae.

 

[jeffmr4]

Looks like Caulerpa going sexual (the white ones anyway).

Video about Caulerpa