Used Caribsea Life rock Help!
 

I recently bought some Used Caribsea life rock and it had some green algae growing on it, but stupid me soak them in water & Vinegar 2L Vinegar in a 5 Gal water for weeks. Now i notice when i scrub with a toothbrush the algae does come off but also some of the purple paint that the rock had before.

I want to continue to remove the algae but dont want the purple/reddish paint coming off from the rocks.

Any suggestion how to keep the paint since i like the color but only want to remove the algae. If i keep scrubbing the paint will continue to come off with the algae. I'm scare when i add to my display tank later on to cycle the rocks will it be reef save since the paint slowly will come off through time or any rubbing friction to it.

Try spraying a piece with Peroxide (regular 3% from the drug store),
you can return it to the tank. It should turn white & go away in a few days.

I will give this a try Thank you!

These items can be removed from the tank. They can be soaked for a few hours in a solution of 50/50 water and distilled white vinegar in which coralline algae is easily dissolved.

The purple paint is likely living, or was. Coralline algae grows on the rocks and turns them pinkish purple. Vinegar dissolves the calcium carbonate which is part of its structure.

The purple paint is likely living, or was. Coralline algae grows on the rocks and turns them pinkish purple. Vinegar dissolves the calcium carbonate which is part of its structure. The bacteria internal to the rock are probably dead or just hanging on. I'd recommend planning doing a full cycle and seeing what die-off may yet remain on the rock.

Thank you , I will try and Cure the rocks for a month in a Clean Garbage bin with a few Power head to rotate the water.