Jelly fish polyps?

[kamberman]

Hello
Last year that I started to add LR to my system, I noticed a piece of rock with some kind of brown "flowers" on it. Month after month these "flowers" begun to spread and now it's almost all over! These things every now and then "crash" (they become like tiny, burned branches, without the "flower") and then they turn back to their initial look and spread. I tried once to wipe them away with my hands, but after a few days they came back, not only where I tried to wipe them away, but also in other places in my aquarium.
I noticed that if they touch corals, they don't burn them or irritate them, but a piece of a montipora digitata that is covered by them has died.
The only book that a found something like that is "The complete book of Marine Aquarium" by Hargreaves where in page 198 he names it Nausithoe cf. punctata and in simple english: "the polyp stage of a jellyfish"!!!!!!!!!!!
Of course I've never seen any jellyfish in my aquarium, but the fact that these "flowers" crash and reform may explain something like that and maybe the baby jellyfish are eaten by my fish, right?

Until now they didn't bother me that much but now that they are all over the place I want to get rid of them and I also need help with their id (incase I'm wrong about the jellyfish story). Does anyone have something like this in his/hers aquarium and how can I deal with it?

 

[kamberman]

After some research on the internet I believe they're hydroids
http://www.njscuba.net/biology/sw_plant-like.html#Hydroid
How can I get rid of 'em?

 

[Mr aqua]

Those are hydroids and they are a PITA.

 

[graveyardworm]

You could try some kind of a guaging tool, perhaps a screwdriver, and set up a siphon tube. As you scrape them from the rocks siphon them out. I have some however not even close to the amount you have, and that method has been working. They do have a fairly potent sting and can injure or kill corals.

 

[charlesr1958]

I feel your pain, literaly, in fact I have been battling these little buggers in my wife's 20 gallon "nemo" tank for awhile now and am at a loss as how to rid them, as such, tomorrow the tank is being stripped down, all rock and sand tossed out, and starting from scratch. yet another good reason to quarantine even rock, gives ya time to look for such things before they spread.

You can try scraping them off, but doing so in the tank is just going to spread them to other areas, as many as you have now, I would think the only sure way to be rid of them is to remove the rock and scrub them off ensuring to rinse the rock with old tank water (good time to do a water change).

Chuck

 

[Mr aqua]

I hear you can blast them with a kalk mix but I'm not to sure as to the method. Since you have a 20G like me, I'm not sure how your chemistry would react to blasts of super concentrated CA.

Another method is to get a syringe of some sort, or turkey baster and nuke them with HOT FRESH WATER, just be careful not to hit any corals that may be near by.

I've noticed that they do have a "weak point" when they spread. I've noticed that they will extend "roots" and not polyp out for a few days almost looking like they are dying. when the "roots" start to reach out you can pull/scrape/suck/blowtorch/ them out easier.

FYI, I have not tried the first two methods but thats the preferred way of removal if you do a search. so far I've been manually removing. its a PITA. need to do research to see if anything will eat them... good luck till then.

 

[Ryanqk]

supposedly you can take a syringe full of buffer or reefbuilding powder and give them "lethal injection" but watch your magnesium levels!