Need help identifying..

[ReefCheef]

Hey guys, hoping someone can confirm what's growing on my rocks. I'm assuming it's diatoms, but would greatly appreciate a few second opinions.

I've had my rock curing in a big rubbermaid tub since the first week of February. I first noticed a few of these orange spots a few months ago, and they havent exploded or done anything crazy, but they are definitely slowly spreading. They have been fish-less cycling while I wait for my new tank to arrive. They didn't have light on them until a few weeks ago.

(trying to figure out what the orange stuff is growing on the white part of the rock)

Please advise!

Cheers

 

[ReefCheef]

bump

 

[ReefCheef]

At a loss for what it could be.

 

[Suohhen]

My best guess would be that it is the stuff that was used to dye the rock. Those areas are bare for some reason, maybe some rock was chipped off to remove coral or there was an adhesive that pulled off. How did you get these rocks? If you're the original owner then I guess those theories don't make sense but it is possible for the dye to transfer as well.