View Full Version : Is it algae?

02/23/2017, 05:29 PM
From the title you get the point. Looks like little zoanthids but are quickly covering my tank. Any ID on them?
https://thumb.ibb.co/djt7RF/20170223_181303.jpg (https://ibb.co/djt7RF)

02/23/2017, 05:59 PM
A little more info. Each "polyp" is about a quarter of an inch in diameter. They only grow on rock and it looks like they only spread through contact of affected rocks. That being said, they aren't ugly. I don't want them gone like HA, but if it's the start of something. I saw a post that they might be Acetabularia. But could use some confirmation.

02/23/2017, 06:16 PM
Acetabularia would have been my guess as well.


02/27/2017, 08:19 AM
Yes Acetabularia! One man's problem algae is another man's dream come true. I had some hitchhike on some seagrass that I brought and really wanted them to grow but they died off in a couple of days.

This is a single celled algae and the nucleus is in the holdfast on the bottom. If you remove the stem and or top part of the algae it can grow a new one.

I would love to have this "problem".

02/27/2017, 08:52 AM
blueCat, I've had the same situation. Mine died within days of introduction. From what I have read, a small minority of people find this species a nuisance while the vast majority can't even get a few to hang around long term.