My tank is brand new (2 weeks old). I added one piece of live rock 2 weeks ago, and 5 lbs of live sand that I mixed on top of the used sand that came with my tank that I bought off of Facebook marketplace just 2 days ago.
After my nightly stare at the tank, I decided to pull up my sleeve and start movsome rocks around in the tank a little. After rearranging some things, I noticed a green stringy leaf like “branch” floating around in the water.
I have been keeping the lights off in the tank for most of the day while the tank cycles, but the tank is in our living room, so at night I have been turning the light on a rainbow setting for a few hours since my youngest daughter enjoys that.
Should I just keep the light off entirely to get rid of this?
Pictures are a little blurry, but what do you think it is, and what should I do about it?
Like I said, my tank is only 2 weeks old and currently cycling so no fish or coral to worry about right now.
Thank you in advance!

After my nightly stare at the tank, I decided to pull up my sleeve and start movsome rocks around in the tank a little. After rearranging some things, I noticed a green stringy leaf like “branch” floating around in the water.
I have been keeping the lights off in the tank for most of the day while the tank cycles, but the tank is in our living room, so at night I have been turning the light on a rainbow setting for a few hours since my youngest daughter enjoys that.
Should I just keep the light off entirely to get rid of this?
Pictures are a little blurry, but what do you think it is, and what should I do about it?
Like I said, my tank is only 2 weeks old and currently cycling so no fish or coral to worry about right now.
Thank you in advance!


