Brown algae?

I’ve noticed some brown algae growing in my tank. It was a newly cycled tank, finalized about 2 weeks ago! Noticed this brown algae during it and it’s easily like quadrupled in surface space. I have ramshorn snails that clearly aren’t doing their job 😭 I ordered netrite snails and all 7 were DOA, so waiting on another batch to come in. I’d prefer not to treat water or use any chemicals. I’ve read this happens with newly cycled tanks but WHY? Also, how do I get rid of it?? lol I have a 14W full spectrum light on the tank (36gal) and a couple Anubis & java ferns in the tank (I added right when tank finished cycling). Pls don’t mind my baby breathing and dog whining in video 😂

ALSO, how can I not want to feed my cute little fancies every time I see them when they get this excited to see me 😭😭😭