What is on this dry rock?? Identification please

Eagle aquatics315 · Apr 27, 2018

Hello guys, I bought a tank from a guy a while ago and got about 100 pounds of dry rock with it. I have been letting them bleach out outside and have cleaned them already. On some of the pieces there is this rust looking color on them and I cant figure out what it is and it doesn't come off. I know it isn't diatoms. The guy claimed it was calcification what do you guys think?? Should I use this stuff??

DeniseAndy · Apr 27, 2018

Honestly it looks like rust stains. Did he have it stored somewhere? When you say cleaned it, what did you do? If I am not sure where the rock was or even sometimes if I know, I will do the acid bath method just to get the top layer of rock off anyway. See if that takes the brown away.

Porpoise Hork · Apr 27, 2018

Looks like organic staining. If you scrape it does it penetrate the rock or is it surface layer only?

Billdogg · Apr 27, 2018

Porpoise Hork said:
Looks like organic staining. If you scrape it does it penetrate the rock or is it surface layer only?

^^^This^^^

I wouldn't worry about it at all if it were mine to use.

AlexStinson · Apr 27, 2018

is that not staining from being under the sand/anoxic at some point, some hydrogen sulfide or something of the likes. IMO it probably harmless as its dry

Eagle aquatics315 · Apr 27, 2018

AlexStinson said:
is that not staining from being under the sand/anoxic at some point, some hydrogen sulfide or something of the likes. IMO it probably harmless as its dry

Yah it looks like the stains are ran along where the rock was under the sand.

Eagle aquatics315 · Apr 27, 2018

Porpoise Hork said:
Looks like organic staining. If you scrape it does it penetrate the rock or is it surface layer only?

It doesnt come off if i scrape it but yes it does come off the rock layer

Eagle aquatics315 · Apr 27, 2018

DeniseAndy said:
Honestly it looks like rust stains. Did he have it stored somewhere? When you say cleaned it, what did you do? If I am not sure where the rock was or even sometimes if I know, I will do the acid bath method just to get the top layer of rock off anyway. See if that takes the brown away.

I powerwashed them and it didnt come off.

DeniseAndy · Apr 27, 2018

Would not worry too much then. Only if you do not like the look.

Eagle aquatics315 · Apr 27, 2018

DeniseAndy said:
Would not worry too much then. Only if you do not like the look.

Thank you I appreciate the feedback

Porpoise Hork · Apr 27, 2018

Eagle aquatics315 said:
I powerwashed them and it didnt come off.

You would have to acid etch it to remove it. Not something you want to mess with as it would take a long time to dilute the acid out of the rock pores. Ignore it as it will be covered as the rock cures and eventually coraline or corals at some point and you would never see it again.

Eagle aquatics315 · Apr 28, 2018

Porpoise Hork said:
You would have to acid etch it to remove it. Not something you want to mess with as it would take a long time to dilute the acid out of the rock pores. Ignore it as it will be covered as the rock cures and eventually coraline or corals at some point and you would never see it again.

Yep thats the plan thanks for the advice.