Danger Says Local Fish Shop!

[kleinfreak]

I showed my little multi-legged critters to a LFS owner and he freaked out...

"Those are a non-coral friendly star and you need them outta there ASAP, buy a pair of Harlequin Shrimp!"

You think this guys got all his marbles in the sack? or is he just trying to hit me up for 18.99x2?

 

[LFS42]

I think they (lfs) are just trying to unload a pair of Harlequin Shrimp.
And get you to come back and buy star fish from them.

 

[smlacy]

I think your LFS thinks this is Aiptasia. I think they're wrong.

 

[Anonymous]

Looks like Hydroid Jellyfish to me.

 

[Anonymous]

There's a pretty simple way to tell if they're stars or not. Are they pentaradially symmetrical? Do they move?

 

[Lostmind]

I have those same things. Do a search on Dr Ron's site - they are apparently perfectly harmless hydroids (type of jellyfish?) and are quite normal in marine tanks.

I just scraped my glass and havent seen them yet - it's been a week.

I wouldnt buy the shrimp, as they need to eat a special diet of starfish, and that would get expensive after a while....

 

[Lostmind]

There's a pretty simple way to tell if they're stars or not. Are they pentaradially symmetrical? Do they move?

Not really symmetrical and they dont move really. Altho I read they can pulse, I couldnt tell if they did in my tank - too much flow had the legs moving around in the "breeze"

 

[kleinfreak]

There's a pretty simple way to tell if they're stars or not. Are they pentaradially symmetrical? Do they move?

Not really symmetrical and they dont move really. Altho I read they can pulse, I couldnt tell if they did in my tank - too much flow had the legs moving around in the "breeze"

Same here.
They range from 4-9 legs. (the in my pic for example is 9)
Move? No, just disappear and new reappear.
They're in my Display, Fuge and Wet/Dry

 

[Anonymous]

If he is trying to help you, ask him rather you can bring the shrimps back after the duty is done...

he probably ask you to buy more starfish from him to feed the shrimps... :roll:

 

[investigator1]

The animals are between one and two millimeters in diameter. These are organisms which are turning out to be relatively common. They are crawling hydroid jellyfishes, which do not swim, but rather move around the tank sort of like a small, soft, slow spider. They move by fastening on to the substrate with their adhesive patches. The tentacles are tipped with concentrations of nematocysts. There is a red eyespot at the base of each tentacle. These organisms become quite abundant in some reef systems, and then rapidly disappear without a trace.

A Japanese researcher, Dr. Yayoi Hirano, provided the following information:

"They are crawling hydromedusae, in the species Staurocladia oahuensis. There are about 15 species of this genus known in the world. All of them have branched tentacles, and can adhere to substrata, such as algae, by the tentacles, with the surface with eyespots facing upward. The tip of the lower branches are used for adhesion, and the upper branches have a few or more (depending on species) nematocyst clusters. Arrangement of the nematocyst clusters is a key to identify species. They reproduce asexually either by budding or fission, so under favorable conditions they often can become abundant in aquariums. This species has been found in a fish farm and also in a abalone aquaculture center in Japan. It seems the species has a high rate of asexual reproduction under favorable conditions. Even one jellyfish accidentally introduced in an aquarium may increase in a population of hundreds within a few months if the conditions are really good. It is also very possible that the polyp stage of the species lives on corals or rocks which may be brought into the aquaria. The polyps may form a dense colony if it is provided with much food. Within a short time the number of polyps may be very large, and the polyps may produce many jellyfish. The jellyfish and polyps will eat Artemia nauplii and copepods.

http://www.rshimek.com/images/RStaurocladia.jpg

 

[fishfanatic2]

I think they're trying to cheat you 40 bucks.

Don't do it. :wink:

 

[Anonymous]

Interesting info, as always, investigator. I think it's impossible to say what species this is based on a photo, but it sounds similar to what he's describing.

I guess "pentaradially symmetrical" is a bad criterion; it's really hard to tell when they're that small. If they're not moving much though, I would bet they're some type of cnidarian.

 

[JennM]

Yes those are hydroids. Have seen them many times. The only time they are really of concern is if you are trying to rear fish fry (ie seahorses - that's when I had a bad hydroid infestation), they will sting and eat the fry as they develop.

Those are in the "jelly" stage - as they grow they can form colonies on the rock and substrate, they look like miniature button polpys. They CAN pack a sting to neighbouring corals, but I've not had a problem in that regard.

Keyhole limpets eat them with gusto. I happened to have some that hitchiked in on my rock and when the hydroid population increased, so did the limpets - problem solved.

To my knowledge, Harlequin Shrimp will ONLY feed on the tube feet of echidnoderms (sea stars). Hydroids are NOT sea stars, so therefore Harlequins wouldn't even remotely be an appropriate "fix" for these.

Jenn

 

[kleinfreak]

That is it investigator1. Thats exactly what I was looking for. That is a much better picture that mine. They were barely visible in my photo, so I reversed the color.
Awesome work.