Help with ID

[mrvn]

Hi everyone!

My tank is only a few weeks old and after all the initial diatoms from the cycle, my rock started getting covered by some sort of green film algae. At this point my nitrates were 5 ppm and my phosphates were 0.03ppm. Anyway, since I was out for a week for vacations my family took care of my tank. However, when I came back I found some brown algae which I though were more diatoms, when I tested for nitrates I got 25 which would have explained the algae but my phosphates were at 0. I’ve tried to feed my fish more to higher my phosphates but they won’t go up and nitrates have remain at 25. I’m concern this might be dinos since I’m able to see some air bubbles in some patches algae but at the same time my trochus snails keep eating the algae without dying. Any ideas?

 

[mrvn]

I forgot to mention that the algae ONLY grows on the rocks the sand bed is completely clean.

 

[obct537]

Obviously can't say 100% for sure, but looks just like the algae I dealt with for the first few months I had my tank. I wouldn't worry about it.

 

[mrvn]

So after some manual removal, the algae appears to have disappeared from my rocks but now it is all over the sand. My nitrates have gone down to 5-10, but my phosphates remain in 0. Something I noticed from the algae on the sand is that it doesn’t have the air bubbles like the one that grew on the rocks. I’ll try to get some pictures later to see if anyone can help me with an ID