build up above filter sponge

[Fish?]

Hello, can someone please tell me what the build up on the surface of my tank is, I'm pretty sure it's from the surface being way more stagnant due to a breeder box breaching the surface of the water. Also there is a thicker spot above my filter sponge and I think it's there because of the stuff on the surface being pushed toward the slits in the back of the tank because I had to lower the breeder box into the tank to let my clownfish back in allowing the water flowing back in to push it there. So is any of this a problem, am I correct, and does this need to be removed. Thank you for the help (pictures attached below).

 

[KrisReef]

Second picture looks like precipitation? Are you dosing alk/calc? Do you know what their levels are at?

 

[Fish?]

not dosing anything, I don't even have any corals yet nor do I test for either level

 

[KrisReef]

I'm out of guesses unless it is the crud that came in with your salt mix? Are you using Reef Crystals? I believe they add clay to the salt to keep it from clumping and it sometimes causes films similar to what you have in mixing containers.

 

[Fish?]

I'm out of guesses unless it is the crud that came in with your salt mix? Are you using Reef Crystals? I believe they add clay to the salt to keep it from clumping and it sometimes causes films similar to what you have in mixing containers.

No I don't use reef crystals, but I don't think it's a problem I just stirred it up and never saw it again