What is this?

[mjenkins62]

Hello everyone, and thanks in advance for your support. I just want to know what this is in my tank and is it harmful. Thank you

 

[silly_blenny]

I'm not the most experienced reefer around, but it looks like a pest anemone (e.g., Aiptasia) to me. It can outcompete and sting corals and spread throughout a tank.

There are several options for dealing with it, including chemcially killing it, introducing animals that eat it, or manually removing it. Someone more experienced than me will probably chime in on what makes the most sense for you in your setup, so if you can give a little more information about your tank that would probably be helpful!

 

[mmorrison55]

Looks like aiptasia to me. If the rock it’s on is small, pull the rock and then scraped it off with a utility knife or something outside of the tank as you want to mitigate any chance of it dispersing inside your tank and causing more to grow.

If the rock is not easily removed, then there are many methods for dealing with aiptasia inside the tank.

But you want to get on it before it spreads.

 

[EnterName]

I second potential Aiptasia and taking the rock out, but I can't recommend scraping it off. Tiny bits of pedal tissue are enough for it to fully recover. If loose bits start floating through your tank you will be greeted with more of these guys soon.

Take it out, treat the rock appropriately to fully dissolve the anemone, and only after it is fully gone and you rinsed the spot thoroughly + brushed it clean, I would return it. Kalkpaste, AiptasiaX, Aip-Away, and similar products do a decent job dissolving these anemones, but treatment outside the tank is far safer than inside.

 

[56longroof]

Aptasia. I inject them with vinegar. Extremely effective.