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

[Vice333]

I am having sort of an outbreak of Serpulid feather dusters that seemed to happen overnight. I have heard that they are harmless, is that true, and does anything eat them? They are all throughout my sump, and I am noticing some on the back of my display.

 

[SushiGirl]

New tank, eh? heheheheh
They're harmless & that's pretty normal. Some wrasses will eat them, but usually they just die off after the initial outbreak. You can just scrape the tubes off later.

 

[markalot]

A white Xanthid crab? I hope!

 

[sieldan]

Snail eggs? (I hope)

Snail eggs? (I hope)

Hey y'all,

Had to run away from the tank for a few days to attend to some family affairs. When we got back, my wife noticed a line of cloudy 'stuff' on the tank glass. We both think that it is snail eggs of some sort. Im hoping so since thats all that the tank has in it right now. Here is a pic. Unfortunatly, the camera wanted to focus on the rock and not the stuff on the glass. Can anyone tell me what this is, and do I need to do anything about it? The only livestock in the tank is a 30gal quick crew from ReefCleaners.Org. (Ceriths, Nassarius, and Nerites)

Thanks!

 

[Mike_Noren]

Asterena starfish. Some say they aren't harmful, others insist they are coral munchers. The ones I've had have only ever eaten coraline algae. I'm stil on the good guys side.

Same here, but there's a large number of species of Asterina and it is well documented that some of them do eat coral. So, keep an eye on them.

 

[Mike_Noren]

What the heck is this? I found it on some live rock that I was putting in my friends tank, it was in a tube made of sand and rock. Is it safe to add back to the tank?

That is what a typical spaghetti worm (Terebellidae sp.) and typical spaghetti worm tube looks like. The tentacles are contracted because you're messing with it, but you can see them as beige spaghetti in the neck region of the worm in the second-to-last picture.

 

[Mike_Noren]

Hey y'all,

Had to run away from the tank for a few days to attend to some family affairs. When we got back, my wife noticed a line of cloudy 'stuff' on the tank glass. We both think that it is snail eggs of some sort.

Yes, cerith eggs.

 

[sieldan]

Yes, cerith eggs.

Cool, thanks. I take it that means Im doing things right with the tank.

 

[Mike_Noren]

ignore. i tried to add that the spaghetti worm looks like it might be of the genus Terebellides and edit time expired. Dear RC, please make it possible to delete posts.

 

[Seagull_3]

Hi all, sorry - I haven't had a chance to take any photos, but hopefully won't be necessary in this case.

About a month ago when I first set up my tank, I had quite a few crabs hitch-hike into my tank off the live rock. I managed to catch & remove all of them, which was a hassle, but manageable due to the fact that there was no fish and/or coral in the tank at the time. Once I put a few corals in, I noticed one more crab, that buried himself in one of my acros - which I proceeded to pull out of the tank & then subsequently killed in the process of removing the crab.

Since then everything has been fine, and I haven't seen any other crabs... until today I just bought another two (large sized) acros from my LFS, and placed them in the top of my tank. Very soon afterwards I noticed 2 x smallish crabs crawling around the base of the coral that I did not notice beforehand. I understand that prevention is better than cure, but I don't have a quarantine tank, and was in a bit of a rush when I put them in. I don't know exactly what type of crabs these are (will try to get some shots later), but do I really need to worry about them, as one of the guys down at the LFS told me not to worry about it last time I mentioned it. I could quite easily remove the acro, but am conscious that I killed my last one doing the same thing (poking & prodding it to get the crab out...)

So... should I just leave it, is it worth killing the coral if I have to, or is there a way I can try to safely remove the crabs? (I have tried the home made traps before & they didn't work...)

Thanks (as usual) for any help/advice...

 

[SushiGirl]

My guess would be that they're acropora crabs. Keep an eye on the health of your acros to determine if you think you need to get them out or not.

 

[Seagull_3]

My guess would be that they're acropora crabs. Keep an eye on the health of your acros to determine if you think you need to get them out or not.

Thanks Sushi I've tried to take a shot, although it's hard to see clearly as they won't come out of the coral. I can see at least two in there, both exactly the same. Guess I'll have to leave them in for now by the sound of it. Can't seem to find a definitive opinion on whether they're good or bad... I imagine that unless the start eating any of my other corals or get big enough to hassle my fish, there's probably no problem right?

 

[cheezischrist]

any ideas on this little guy? he was 1/4 inch sunday, now almost a dime. lives in a small cave in just the one rock. i removed him from that rock after this pic last night, to a rock pile on the other side of the tank, and this morning he has returned to his rock . doesn't seem to have a preferance for night or day either. sorry for the blurry pic, my phones camera isn't the best. thank you

 

[Mike_Noren]

That's one of the numerous species of small starfishes which routinely get identified just as "Asterina" - and it may well be an Asterina, it does look the part. It's not the standard, gray, asexually reproducing half-inch and almost certainly undescribed Asterina found in nearly every reef tank and usually identified as Asterina anomala, it's some other species, and the unusual pigmentation might mean that someone who's good at starfish may be able to identify it to species... But I can't.

I can tell you that it probably does not reproduce by fission (because it's symmetrical, unlike the small standard species), so you probably will never get very many of it, but while most Asterina eat biofilm and algae some do eat coral, so you might want to keep an eye on it.

 

[cheezischrist]

thank you, keeping an eye on him will be simple for now, the small rock he stubbornly lives on is right up front by itself, and being one of the only visable lifeforms in my tank currently, my girlfriend stares at that rock for ages waitin for him to come out of his cave and make passes around the rock. he doesnt move very fast either. hoping he gets bigger so i can more easily identify him, and stays his coloration, and also turns out to be keepable lol. that photo isnt the best but hes kind of a real pretty green, with orange tips and small dots. i probably wont even begin to start to add coral for at least 6 months, probably more, as well, im still planning on collecting another 20 or more lbs of lr over the next month from all over the place. thanks again

 

[cheezischrist]

how bout this little yellow guy?

 

[Pete H.]

looks like a yellow polyp - Zoanthid coral. (At least to the untrained saltwater hobbyist eye)

 

[cheezischrist]

ha thank you. id like to see the little guy spread and make it through the rest of the cycle, wich test results say is done, but i dont trust it cus its only been a week lol, and im adding a ton more rock this weekend, wich will probably crash the system all over again. ha fingers crossed

 

[SushiGirl]

Thanks Sushi I've tried to take a shot, although it's hard to see clearly as they won't come out of the coral. I can see at least two in there, both exactly the same. Guess I'll have to leave them in for now by the sound of it. Can't seem to find a definitive opinion on whether they're good or bad... I imagine that unless the start eating any of my other corals or get big enough to hassle my fish, there's probably no problem right?

About the only thing you can do is google acropora or acro crabs and see if any look like yours.

 

[mmmm4life]

New guy needs answers

New guy needs answers

Hey all new to the coral tank world for myself. Brother has been doing it for years and has it down but I have a question for anyone able to answer. I have only had my tank up and going for about a month or so, and have extremely well cured live rock that was intrduced to my tank but have what seems to me green coralline algea growth but its very rapidly growing along with the purple. I just want to know if there is a possible bad green item that this could be. I have been useing B-Ionic chem. daily and have heard that this stuff may make the coralline algea growth be this rapid. Any input is good input. Thanks