In a few places on the rock
there is a greyish looking algae growing in a few spots and getting worse.
Could anyone advise me what that maybe.
The rock is fouling from the die off, it is very common in curing LR
. As the rock continues to cure, it will go away. I have found it useful while curing LR
to do water changes to aid in preserving the life on the rock from rising ammonia levels.