What is this?

[trinityh13]

What are these? They are all over my dad’s tank but I wasn’t fully sure what they are, are they good or are they bad?

 

[trinityh13]

What are these? They are all over my dad’s tank but I wasn’t fully sure what they are, are they good or are they bad?

I’m guessing hydroids? They have been in the tank for a little bit apparently but never have gotten bigger than in the picture. If unwanted how do you get rid of them?

 

[Gumbies R Us]

@ISpeakForTheSeas

 

[IKD]

Look like colonial hydroids.

 

[mwil79]

Yup I agree, Colonial Hyrdoids.... good luck.

 

[IKD]

Generally a pest as they spread easily. And they stink to high heaven out of water. I generally hand-picked them with tweezers for small amounts but may want to pull the rock and dry out with the quantity you have.

 

[ISpeakForTheSeas]

@ISpeakForTheSeas

they're either colonial hydroids or Nausithoid jellyfish polyps (probably from the Nausithoe genus):

to my knowledge, they're not invasive (or at least not always), but they reportedly do have a nasty sting for some people

For removal ideas:

No personal experience with removal, but this is what I've heard on removing them (keep in mind there a lot of different species of hydroids, and some may respond to one treatment while another may not):

I've heard smothering the hydroids with kalk paste may work, but here are some other threads with suggestions that might be helpful:

Hydroids: a reference to some strategies

Like many of us, I have had problems on and off over the years with Hydroids. The ones that have always given me the most problems are the common ones that almost look like a smaller and darker version of the beginner coral called Yellow Polyps. But the colonial Hydroid is much smaller than...

www.reef2reef.com

Hydroids - How do I eliminate- They have taken over my tank

So I have this stuff that has pretty much taken over my tank and I can't get rid of it. I'm looking for an ID and an eradication plan that is anything short of a total teardown.

www.reef2reef.com

Fenbendazole dip for blue clove polyp/hydroids.

FYI So I had more than few blue clove and what i believe are hydroids pop up on a few frags and start spreading in the frag system. I didn't want to start out treating the whole system so I picked the most populated frags to treat. I mixed 1/4 gram of Fenbendazole with 1 cup of saltwater as a...

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Edit: A relevant link in post 7 of the link above:

Here it is! Fenbendazole use against hydroids

Hi all! Well after getting a lot of questions about the use of fenbendazol I figured I would write this up. This is for informational purposes and I will not be held liable for improper use. Fenbendazol must be used exactly as I instruct or run the risk of a tank crash. Now lets get to it! So...

www.reef2reef.com