Anyone seen this?
 

I have a black bubles forming (growing) on a peice of live rock, they range in size from a tear drop to the size of a marble or thumb nail. They are very glossy black and hard to touch but can be slightly depressed...I stress they are growing? (slowly)

Who is the imposter in Ranzreef? :roll: :roll:

Sounds like it could be Valonia, also known as bubble algea.

bubble algea
 

Dale is bubble algea hard like a rock?

Randy

They can be fairly hard. If you squeeze them hard enough they will pop. They are usually dark green or black and are often shiney.

Would sure help if you could post a picture, but it does sound like algae. Each one is an individual cell I believe, if you pop it, you get more, as long as it isn't out of control they are kind of attractive, some animals will eat it if you want to get rid of it.

It sure sounds like Valonia. They are different sizes, quite tough, with dark green-blackish colour and look like beads or marbles. There are mixed opinoions on the whether the "popping" of them is harmful or not but just play it safe and leave them.

Ranz, if this is valonia, you should be able to roll a larger bubble off of the rock. Take it out of the tank and pop it. If it's a hollow "bubble", it is most likely valonia. If it isn't hollow, it's something else. I have some and it isn't black, but rather green.

Here is a pic..

http://www.globaldialog.com/~jrice/a...ge/valonia.htm