Something strange is in my tank

[Mike&Pam]

I found the strangest thing on top of one of the live rocks today. It was a little ball, about 2 cm in diameter. It looked like a grape, only a little smaller. It was like an olive purplish color, just like a grape. It had a hard shell and smooth texture. What could this be?

 

[slojmn1]

Just a guess as your picture did not come through. Valonia with some coralline growth on it?

 

[Mike&Pam]

How about now?

 

[cat23]

Looks like bubble algea. Get rid of it! Not good to have. Often you will see this in a new tank. Just pick it off the rock and try to get it out.

 

[Anonymous]

Looks like Valonia(bubble algae). I have some in small patches. They can be a problem in high nutrient tanks.

Dan

 

[slojmn1]

Yup, Valonia. I have it in my 120g reef and try to pull the balls out without breaking them in the water. Supposedly the spores will be released if you break them in the water and more will grow. They will also eventually break on there own. I saw one once in a lfs the size of a softball. they had had it for years in one of there reef displays, it just grew and grew and never broke open. There appear to be two variations in my tank, lucky me, the type in your picture. More rounded with one main ball. the second type are smaller clumps of valonia, like grapes on the vine in various shapes. There will be a clump of them growing, maybe 10 to 12 small and elongated. I can detach these clumps very easily. the problem is a small rougue valonia will easily break off and get away from me. The large single round ones can be attached to the rocks a bit more secure. Eventually they will grow large enough that you can pry them off withoput breaking them. I would try to get rid of it. I pull mine out as soon as I can easily dislodge it from the rocks. Interestingly enough, most people that look at my tank oooh and ahhh over the valonia, lol, go figure.

 

[davelin315]

It's valonia or bubble algae like everyone said. I don't know why it's so undesireable, though. I used to have it in my old tank and it grew in really neat structures, almost like tree and fan sponges do. I have a bubble here and there in my tank now, but it doesn't hurt anything, and in fact, I wouldn't mind some more. You'd be surprised at how often people come over and tell me one of my clams spit out a pearl.