Most leather type coral actually go though a molting phase where they will appear to be gray & slimmy. They will produce a mucus film on them & if not moved in to more direct flow for a temp period they can stay like this for some time, it's a normal phase they go through as they grow. If you can't or don't want to move it put a small power head directed at it until you notice that it is returning to normal.

Mine also does this, comes back in a couple days looking even better

I had my leather for over 3 years until I added bio pellets. Killed it in 2 months.

Thank You guys. Now is the fourth and still the same. Hope it better soon.

I have been running bio pellets for better then a yr and my Devils hand is huge as well as my Colt coral. I really don't think it was the pellets maybe it was the way you started them.

Could stay like that for as long as a month, my Devils Hand took that long once.

oh boy

Did you direct a little flow towards it to help remove the slime coat?

I didn't see any slime coat.

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