ID: Do I have a Brown Hydroids?

[Pwnm30rdi3]

I left town for 3 weeks, while I had a friend take care of the tank.
When I returned I found these guys on 3 or 4 of my rocks.

I don't think they were there before, or maybe they were and I wasn't paying attention. Preliminary searching has led me to believe that they are Brown Hydroids. They do have a stalk that looks to attach to the rock. I haven't tried hand removing them yet. I'm not sure I'm properly IDing them.

I added a few new pieces of live rock about 9-10 months ago from a reputable source. I think they may have actually hitched a ride on a frag plug, the frag is for sure the culprit to my aiptasia problem.

My tank husbandry has been lacking this last month. I did my first 25% water change in 6 weeks.

A little history on the tank:
Main Tank is 100 gallon & 50 gallon Display Fuge with a 30 gallon Sump.
Tank is 8+ years old, very well established.

What is the best method to remove these mysterious polyps?

http://i.imgur.com/eyFZIjLl.jpg
http://i.imgur.com/7cVvOvol.jpg

Thanks!

[thedasher]

Aiptasia get rid of it quick before it spreads ,I used peppermint shrimps and they got rid of in a day or you can use Aiptasia x

[cloak]

Yeah, they look like Colonial Hydroids. If you want to get rid of them you could always smother them with some epoxy. Just as an example, all that epoxy in the picture below was used to smother some blue clove polyps.

http://www.lionfishlair.com/hitchhiker.shtml

http://i172.photobucket.com/albums/w16/jAb83_2007/smother_zpsexdtosnj.jpg (http://s172.photobucket.com/user/jAb83_2007/media/smother_zpsexdtosnj.jpg.html)

[thedasher]

Oh I was looking at the wrong thing sorry, the second picture the thing on top is the aiptasia

[Pwnm30rdi3]

Yeah, they look like Colonial Hydroids. If you want to get rid of them you could always smother them with some epoxy. Just as an example, all that epoxy in the picture below was used to smother some blue clove polyps.

http://www.lionfishlair.com/hitchhiker.shtml

http://i172.photobucket.com/albums/w16/jAb83_2007/smother_zpsexdtosnj.jpg (http://s172.photobucket.com/user/jAb83_2007/media/smother_zpsexdtosnj.jpg.html)

I've thought about just epoxying over them, but I don't know that I could live with that large of an epoxy glob.
I suppose coraline would quickly cover it up.

Turns out my Nitrates are quite high. I tested my RO/DI water and it came back at 40ppm. I guess it has been about a year and a half since my filters were changed... Whoops.

[Radioheadx14]

use the epoxy to kill/smother them and then after a period of time (not sure how long it will take to kill them) you can remove it... epoxy doesnt stick well most of the time.

[mussel and hate]

Definitely coronate scyphozoans (Nausithoe?). People tend to refer to them as hydroids though I don't think that is an accurate ID.

I've had these in my tank since the 80s. While they are near impossible to eradicate I've observed hungry emerald crabs munching on them. In fact at one point I could not see any left. After the demise of said crab they have returned.

These jellies haven't caused any problems that I can detect. I've seen no evidence that they impede colonization by the various corals I've maintained except perhaps briarium.

Their tentacles fluoresce green under blue or violet light. I suggest you just imagine that these tiny polyps are benign and enjoy them. They aren't going away.

[Pwnm30rdi3]

I just picked up a few emeralds today. I am not keen on covering my rocks with epoxy, but I might if they seem to take over.
I've read that many people have luck with waiting it out, as opposed to fighting them.
I'm hoping getting my parameters back in check and letting these emerald crabs go to town help!

Images of coronate scyphozoans seem to match perfectly. Thank you!