New live rock good or bad algae?

I just purchased some new rock from a guy and it is a very nice shape that will fit my aquarium well.. We have went over it with a "fine tooth comb" in an attempt to avoid a headache with my newer tank...

It has a lot of green algae on it and I am trying to determine if I am going to add it or toss it in the garbage... I am posting a pic and maybe you can help me decide as I dont want troubles for a new rock... If it is bad rock will it be ok to add or shoudl I through it away...






Thoughts ?

 

check out the peroxide thread

 

I am unsure.. Thats what I am trying to figure out.... How can I tell?

 

Looks to me like green coralline. Does it rub off easily?

FWIW, coralline will grow most anywhere and comes in a variety of colors. Cal, Mag, and Alk levels along with light spectrum and intensity determines the actual colors that will be dominant in your tank. If it was green in the other tank, it may bleach then come back in a different color once it acclimates to yours.

 

I scrubbed it with a toothbrush and it did NOT rub off at all....

 

i had some of those same rocks in a small tank of mine for hawaiian volcano shrimp, it didn't spread onto the sand or glass with mine

 

where is the peroxide thread?

 

Thanks for all the quick help