Clean algae off used rock

[Similar]

Hi all I'm new to reef aquariums and purchased a tank from someone that came with some rock.

Is there any issues in using this rock as it is stained green (refer images) - i.e even though this rock has been unused for over 12 months, would these stains cause it to regrow? If so are there any relatively quick treatment methods? In my research I've seen people using either vinegar or bleach, but I'm hoping whichever method I use it won't take more than a week as I'm keen to fill up the tank!

Many thanks

 

[dwest]

Personally, I would rinse it off and use it. However, you can use bleach to remove the green, just be sure to read up on bleaching to ensure bleach is removed before you use it.

I don’t think that algae would ”regrow”. However, you are gonna get algae just like it, and likely others, after it’s been in your tank for a while.