Subject says it all. I made the mistake of buying some coral from one of our former LFSs (I won't mention who, but he was the "revolutionary" shop in town) that had quite a crop of them on the rock. "No problem," he said, "they'll just go away after a while." Not a mistake buying from there...ever...just buying **THAT** particular coral.

Ok, so a year and a half later and I'm battling these beasties continuously to keep them from taking over the tank. I've tried just about everything I can think of and searched the Internet for clues. I got nothing here. The best success I've had so far, is simply plucking as many as I can and then shooting the area with turkey baster and boiling water. I loose the coraline in that area, but it does seem to do a number on the hydroids. The coraline will grow back, but I'd really rather not lose it to begin with.

Does anyone know of a magic bullet to rid your tank of hydroids?

what kind of hydroids are you talking about? I think that is a general description for several critters like spaghetti worms, little jellyfish type things and an aptasia looking pest.

I've seen a lot of suggestions for kalk paste and/or tweezers depending on what you have.

I'm not sure you'll have a choice but to kill coralline if theses are attached well.

These are the brown "pom-pom" looking things. They're actually rather cool, other than they spread like crazy. I've picked and plucked and preened with tweezers. I can make a serious dent, but they always come back. What I have discovered, is that you also have to get the lattice-like "root" structure...not just the top pom-poms. I've been exploring alternative methods lately and am actually having great success getting rid of them in specific areas by first picking with tweezers and then blasting the area with boiling water. I lose the coraline in that area, but it really does a number on the hydroids. This is a fairly recent experiment, though, so I really don't have any feel for it's long-term effect. Time will tell...

Preparation H :D

That only shrinks them and temporarily relieves the itching. To truly remove them completely, though, requires a hydroidectomy...but that's a major pain in the a**, so I'm told.

lol

I wonder if a peppermint shrimp or a copperband would go for them since they are similar to aptasia and yellow polyps.

Though, since they have that root structure, I'm not sure if they'd just return like with the tweezers.

Even if they did return it would be a just a food source for the copperband or Peppermint. I would like to know if they do eat them.

nope, and nope...

We've tried everything under the sun for these little !@#$%^& and nothing works. The only thing I've ever seen work to an extent are berghia nudis, but their expensive and you need ALOT of them..

We had a couple of peppermints in there for a while, but that was before the hydroids really took off. We tried a pearlscale, but that turned out to be one mean butterfly...gave our SOB pygmy angel a serious run for his money. Plus, it developed a taste for mushrooms and was beginning to do some real damage to some of our nicer multi-color bumpy mushrooms. It had to go before it got roasted over an open flame. Funny, I'd always had an impression that butterflies were these timid critters that you had to almost force feed. This beast beat up the meanest fish on the planet and then started eating everything in sight. Who'd uh thunk it?!?!?!?

While not exactly pretty at first, I've had luck just putting epoxy or super glue on top of them. I tried Joe's Juice, which had a minor effect.

Interestingly enough, I credit the same shop for the introduction of mine.