What kind of media is this?

[NewRobert]

In my ongoing rescue project (https://www.reef2reef.com/threads/roberts-180l-rescue.807270/#post-8648585) I am curious if anyone knows what kind of media this is that came with it:

(Please excuse the plane shavings and sawdust in there, busy refinishing the cabinet first and lacking space to keep things clean)

Or is it just rocks thrown in the sump?

 

[homer1475]

Looks alot like seachems denitrate, which is just rubble rock.

 

[fishguy242]

hi,looks like rocks to me,they were "alive" at some point,either have to cure as dry rock or discard,honestly i would remove,go with a porous rock or media,these seem dense. happy reefing...

 

[Beau_B]

+1 for seachem media.

it’s not expensive so I would vote for buying new if you wanted to have some.