Ammonia levels and brown stuff on rocks

[Hetts]

So first what is this brown looking stuff on my rock, my tank has only been setup for 2 weeks and I have 2 clowns and 4 blue legged hermits. I used turbo start 900 to help boost the cycle. Also my ammonia levels seem to be around 0.25 ppm is this bad? I know it would be best at 0 but I’m wondering if it’s at 0.25 ppm due to uneaten food in tank. Any help would be great, thanks!

 

[JohnGP]

Those are Diatoms and they're normal for a new tank, they will eventually go away in a couple weeks. I wouldn't bother trying to clean them out, they'll be back the next day. Just let nature take it's course and all should be well soon. You'll start to see your ammonia drop soon, patience Grasshopper.