What would cause brittle rocks?
 

I have Marco rocks that have been in my system for 2-3 years but over the past year they seem to have become super brittle like I can break pieces off and scrape layers off them only change is I started running my ca reactor again but ph of the tank is the same as before when I was dosing. Any ideas?

Anyone?

Endoliths are going to be dissolving any calcium carbonate substrate even at the high pH many of us keep our systems.

I’ve read Marco rocks cause brittle rocks. Number one complaint I read about those rocks from day one when people bought them.


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How did you cure and/or start the cycle? I've read a few places that acid or bleach baths will remove rock. Pukani comes to mind.

It is probably the composition of the rock from where they were terrestrially collected.

Super low PH can also make rock brittle, but we are talking about in the 6.X range.

Tank runs at 8.1-8.3

No acid baths or anything like that