Pix & ID: Critters that come in your rocks: the good and the bad.

[Ryphen]

I believe they're called ball anemones. They can sting and have been known to spread quickly in some tanks. Some people treat them like aiptasia and eradicate them as they see them.

 

[hogfanreefer]

I believe they're called ball anemones. They can sting and have been known to spread quickly in some tanks. Some people treat them like aiptasia and eradicate them as they see them.

This has a stony skeleton (that central disc is hard as a rock). I didn't think anemones did?

 

[SushiGirl]

Lammy, looks like it might be a sand skater or something along that type of pod. Markings are cool on it. Sand skaters are harmless.

Hogfan, I've never had a plate coral, but that's still my best guess going by all the pics of baby plates I've seen on here. Any LPS with tentacles can sting so as long as the zoas seem out of reach & fine they should be ok where they are. Not sure at what point you should move it to the sand. You could try reconfirming the ID on the LPS board or run a search on baby plates. Lots of threads out there IDing them & advising when to move them. It's definitely not a ball anemone...I'm the ball anemone queen OL.

 

[Rob in Puyallup]

Any idea what this is? I just noticed it several days ago on a piece of coral rubble.

 

[alexander_ktn]

It's a vermetid snail.

 

[Rob in Puyallup]

Oh... I just read up on those. Not good news, I guess. Should I get rid of it?

Thanks

 

[alexander_ktn]

As long as there are only a few they don't really harm anything... You can at any point break them off or glue them shut if they become a nuissance.

 

[Foxxy]

Hi, skimmed as many pages of this massive thread possible, but still need 2 ID's.
The worm/slug thing is almost 2" but shrinks to near nothing and goes back into the rock. It's white w/ black stripes and red antennae tips. The crab I assume is bad but can't get him out. He hides in a hole and waves a claw at my cleaner shrimp when he passes by. It's yellow, darker claw tips, appears to eat rock :/

 

[Foxxy]

K well I guess I can't edit my other post? put up the wrong link, and none of my other pics will load, I got a site error message and don't have time to mess with it anymore tonight lol, so just attached smaller ones... Thanks for any help!!

 

[Rob in Puyallup]

Thanks, Alexander. I'll be watching!

 

[alexander_ktn]

Foxxy, the first one is a species of Thuridilla, those are algae eating nudibranchs.

As for the crab: I can't say...

 

[SushiGirl]

Glad Alexander could ID the slug LOL. Crab kinda looks like maybe a Xanthid, pic is pretty blurry. You could try a small glass tipped up against the rock with some food in the bottom to try to catch it if you haven't tried that already. It's probably picking at the rock for algae. Crabs will eat pretty much anything.

 

[Foxxy]

Glad Alexander could ID the slug LOL. Crab kinda looks like maybe a Xanthid, pic is pretty blurry. You could try a small glass tipped up against the rock with some food in the bottom to try to catch it if you haven't tried that already. It's probably picking at the rock for algae. Crabs will eat pretty much anything.

great thank you both! So for now, if the slug sticks to algae, he's ok to keep. I have a couple great close-ups of the crab, but that's what I couldn't get loaded yesterday. As for the glass trick, well keeping the shrimp from eating anything before 5 minutes is a problem haha.

 

[Salt_waterlover]

Very helpful!

 

[SweesFeesh]

Green Lipped Mussel

Green Lipped Mussel

Sorry that I don't have a pic, I'll try to get one later. Found a green lipped mussel on a rock I bought about two months ago. It just appeared there. I had seen the spot many times before, then this appeared. Very weird. I don't know how its still alive.

 

[tatuaje08]

Looks white in the tank.

 

[alexander_ktn]

Looks white in the tank.

It's a chiton, an algae grazing snail.

 

[alexander_ktn]

is there bad or good critters?

Very philosophical!

But there are certainly critters that can harm what we have in our tanks or help with problems.

 

[SweesFeesh]

So many people hate Eunicid worms because of their destructive feeding, but they are actually extremely interesting. Like mantis shrimp, if given a species only tank, they will be interesting and occupy your time. They don't only eat corals, they also eat dead animals and left over food. Before just killing off your eunicid worm, at least consider giving it a tank of its own.

 

[Flashy Fins]

Spotted this dark colored thing in my tank; seems nearly black in reality, but showed up brown in the pictures. It was still for a while, but as I turned lights off and back on a couple times in an attempt to get decent pictures, he started moving. Speed was comparable to a snail. Starfish missing legs, maybe? Good or bad?

Thanks for your input! Learning a lot from this thread, although it's taking me some time to get all the way through it.