Is this normal?

[Johnny bass07]

I set this frag tank up 3 days ago and I used new saltwater. There isn't any light and I have not put anything in the tank. Should this filter sock be this brown in a new tank with nothing in it?

 

[X-37B]

I would say no. Thats really strange. I would remove it and add a new one and monitor it.

 

[Cell]

Did you mix the salt in the tank? What brand if salt? Some leave brown residue.

 

[Goaway]

That is a lot of brown. Odd.

 

[Johnny bass07]

I would say no. Thats really strange. I would remove it and add a new one and monitor it.

Could the reef crystals salt cause this? I do notice after it sits in a bucket a couple days there is a brown film

 

[X-37B]

Yes but its unusual. When mixing IO in a brute container I add a 1/4 cup of rox carbon. No brown anywhere and it mixes crystal clear.
I would just replace the sock and through in a small nylon bag of carbon and call it good.