Noticed something new

[oro50]

I have 15 lbs of live rock in my tank. A 20 L tank, which at this point I believe is cycled or almost cycled.

Just happened to notice though (the other day tested for nitrates) it was blood red, 160 ppm according to the test kit chart I use.

Anyway, noticed on a big flat piece of live rock I must have just put in two weeks ago, that one of it sides now is green. A shade of green that can appear on very old pennies.

Just wondering if this is new algae?

Secondly, I'm wondering if this new algae growth is due to the high concentration of nitrates that seemed to exist in my tank when I took a nitrate reading two days ago?

 

[thirty6]

You should do a nice water change this weekend and follow up with another during the week or next weekend again and see what your levels are at. Algae is normal and will probly have another bloom at some point. Start thinking about your clean up crew (cuc)
Give you something to look up and decide on

 

[Nandez13]

Yes, it's algae. Move your rocks around and you'll see they turn that color where the light hits them. Elevated nitrates/phosphates do result in algae but it's fairly normal for a new tank that's still cycling.

Are your ammonia and nitrite levels at 0 now? If they are, I'd start doing weekly partial water changes. If these two parameters are still detectable, then I would wait before doing a water change and just let the tank do its thing. Make sure you get your nitrate levels down before you start adding anything though. How long are your lights on right now?