Aquarium Gravel Stained

[mpertz]

I have a question about my aquarium gravel. It seems to be stained or have some weird coloring on it and I have no idea what it is. My Aquarium water quality is good. I just tested it. Temperature is 78F. The aquarium is 5 gallons, so pretty small and I set it up Mid July. The gravel is lime green and has brownish stains in small groups all over the tank. Just noticed this a few days ago, was never there before.

Any idea what this is and how I can remove it.

I attached a picture to show what it looks like

Thanks for the help,
Mike

 

[mfdrookie516]

Cant really tell much from the pic, but it almost looks like diatoms, which it more than likely is. See if it comes off pretty easy by rubbing it off with your fingers. It's very common in new setups, i still have problems with it in my 150g thats a year old