Was the rock kept wet? My liverock for the tank I started with had rock in old rubbermaids...guy kept water over them for a couple months, and I got somethings growing out of it. Mainly coraline algae. Dont know if that would have just gotten into my tank anyways though, like marine algaes.
At this point I would buy a small ammount of high quality LR to seed the tank with. None of the FL farmed crap if it were me.
Fitting 600# of LR into a 300g tank might be a little much. Dont be afraid to use less instead of more, as long as your rock is porous and there is a lot of it you should be fine.
Lets see some pictures of this 300g! What are your plans for it?
At this point I would buy a small ammount of high quality LR to seed the tank with. None of the FL farmed crap if it were me.
Fitting 600# of LR into a 300g tank might be a little much. Dont be afraid to use less instead of more, as long as your rock is porous and there is a lot of it you should be fine.
Lets see some pictures of this 300g! What are your plans for it?