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Sk8r 11/16/2011 11:23 AM

Pix & ID: Critters that come in your rocks: the good and the bad.
Generally---you WANT tiny life in your tank; a lot of it: a flashlight after dark should show you a LOT of critters on your sand.
Keepers: Good Guys bristleworms, spaghetti worms(in fact ANY worm, except one, listed below under bad guys). Spionids are fine. They're cleaners, like other things.
Mysis shrimp, tiny tiny tiny shrimp that make you think they're baby fish. Free fishfood.
Copepods and amphipods---copepods are white dots that move. Amphipods look like rolypolys or sow bugs. They do not have visible eyes! [if you see on of those, it's bad!] Again, free fishfood, and you can't have dragonets withOUT them.
Snails, stomatellas (saddle-shell snails). Chitons. Limpets. Wonderful guys. I'll add: strombus grazers, little snails that spin silk and use ropes to get where they're going.
Sponges (water filters). Occasional weird growths like networks on your rocks. These are great filters and improve water quality.
Occasional patches of algae that won't last long. In general, confine plants to your fuge. They block light, shed, and make problems.
Shrimp: cleaner and pistols, with caution: If you hear clicking in your tank---bad news. Pistol shrimp often kill fish. Pistol/goby pairs can end in the death of other fish in the tank. I had one kill its own roommate.
Micro-hermits with bitsy claws are fine. They walk on corals, but don't harm them. Neither would you, if you weighed that little.
Asterina stars: little starfish with a short leg: generally harmless Micro brittle stars, big brittle stars. All nice little cleaners.

Bad guys:but even these are ok in your sump I recommend AGAINST any crab but micro-hermits, whatever. Ever. Ever. Interesting to watch, but they need their own tank. Period. They eat fish, or other valuable things.
Shrimp: usually bad news, unless you want a mantis or pistol, and they're great specialty creatures: clicking in your rocks---pistol. Fish are in danger.
Eunicid worm: looks like a centipede with obvious tentacles on its head. Starfish in general. Green serpent stars.
Caulerpa algae: any rock that has it should be discarded.
Isopods: a cirolanid isopod looks like a roly-poly (sowbug) with obvious slanted black eyes. It attacks fish.
Flatworms--like the Star Trek emblem, a comet-thing on your glass or rock, with a forked tail.
Aiptasia, majanos---little 'volunteer' anemones, brown, nuisances.
Hydroids, look like a yellow-brown little mat of fuzzytopped sticks, about the diameter of a needle, about a quarter inch long. THey sting. Not nice.

In general, if you're in doubt of a hitchhiker, put it in your sump after posting a picture of it. Most things that don't go nicely in a tank can live a useful life in your sump, eating surplus food and detritus. A lot of neat things like barnacles, tunicates, and little clams don't last long in our tanks. Wish they did.

redneckgearhead 11/16/2011 11:47 AM

Asterina stars can be bad and should not be put in the sump. I did that after I brought two home only to find out a few days later that they had eaten a ton of corals at the LFS that I had gotten them from. Yep you guessed it I now have them in my tank and every morning before work I scout my DT out and pick them out with tweezers. Occasionally I find them on my zoas.

Sk8r 11/16/2011 12:49 PM

Mmm, let's add that if you have softies, they can be a problem...or at least that there is a species of asterina that is predatory. It would be hard for one of these to transit through a pump to the DT, but it could happen.
Mine occasionally leave a brighter pink track across my coralline. That's all. And there aren't many.

Sugar Magnolia 11/16/2011 02:59 PM

Not all isopods are bad. Sphaeromatids, look similar to cirolanids, but can curl into a ball when touched. Cirolanids can not. Sphaeromatid isopods are harmelss detriivores.

Sphaeromatid isopods:


For comparison:

Another example of harmless isopods is the munnid isopod, very commonly seen in our tanks.

Sk8r 11/17/2011 10:12 AM

Thanks for those pix. Never have seen one of those guys. My cheato moss is so tame, in the pod department. But I have an amazing collection of limpets.

reeflip80 11/17/2011 11:52 AM

Great info Sk8r, thank you! Tried to bait a xanthid crab to a cup last night and he had me in suspense so many times...moment I thought he'd dive right in, he hides back in his hole! :angryfire: lol Maybe I'll try a piece of silverside tonight instead of krill...oh and just noticed last nite too, I have another smaller crab feasting on my rock.

Sk8r 11/17/2011 11:59 AM

Thanks! Let's see if we can get some more pix into this thread: it's real helpful to have photos.

WetShepherd 11/17/2011 02:49 PM


Originally Posted by Sk8r (Post 19526422)
Thanks! Let's see if we can get some more pix into this thread: it's real helpful to have photos.

Mithrax? Pulled a dozen of these out of my tank when it was cycling - took a month to get them 'all'. Then just a few weeks ago (6 months in) I turned up a 13th. It was dead near a new torch I'd added - no idea what killed it. Presumably it was killed by something as it was out in the open.

It also turns out I think I have a eunicid worm as well. I've seen it twice but assumed it was just a bristle - would have been easy to grab him if I'd only known - so THANKS for this post. I know now and I'll watch for him. I'll try to get a pic up later.

SK8R's NOTE: look at those big claws. That's trouble. Sump!

Sk8r 11/17/2011 03:13 PM

Just because everybody needs to know a bristleworm when you see one: meet Sam. I lost him in a move, along with Frodo and two others called Fred and Barney. These larger ones tend to have one hole in one rock and to pretty well stick to it, but they are really great cleaners, and I greatly miss these 4. All my current ones are little guys.

Sk8r 11/17/2011 03:29 PM

Corals can be mean

Note the string coming off this bubble coral. That's a 'sweeper,' or stinging tentacle, and this is why you don't put stony coral within 6" of any other coral, downcurrent. This coral is annoyed because it smells another coral on the ledge above it.

Sk8r 11/17/2011 03:31 PM

Snail eggs. Some live. Some get eaten by fish. MOST get eaten by fish, or we'd be hip deep in snails. Unfortunately the ones you hope would reproduce successfully seem to be particularly delicious.

Joe0813 11/17/2011 04:11 PM

thanks sk8r.... question though... my tank is not up and running just yet. but when it is are those little pod things in the pictures even visible with a naked eye? or do you need to hold up a magnifying glass

Sk8r 11/17/2011 04:54 PM

Oh, those are magnified. The tiny white copepods are about the size of two grains of salt together. But they move. And if you look real closely they have legs. The larger amphipods are about the size of a sowbug, or rolypoly, but many are about half that. Mysis shrimp, which you may also see, usually are about the size of a little black wood ant.

Joe0813 11/17/2011 04:59 PM

ive seen the mysis shrimp at my LFS... but ive never seen pods... yet, the owner said he would give me a tour of the big fuge he has down in the basement. so im sure i will see some fun things in there

Sk8r 11/17/2011 05:26 PM

Actually if you look closely at the glass in the snail egg pic, there's a white dot. That would be one. ;)

SushiGirl 11/17/2011 07:17 PM

5 Attachment(s)
Aiptasia (some are lighter, some are dark)
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Bubble algae (valonia)
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SushiGirl 11/17/2011 07:25 PM

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Cerith snail with isopods on the glass
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Cerith snail eggs
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Collonista snail
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Eunicid worm (sold to me as a medusa worm)
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SushiGirl 11/17/2011 07:29 PM

5 Attachment(s)
One variety of hydroid. There's a huge variety of hydroids & they don't all look alike. This kind turned into the little jellyfish shown.
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Peanut worm. They come in a variety of colors and various feathery head types.
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SushiGirl 11/17/2011 07:32 PM

5 Attachment(s)
Pineapple sponge
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SushiGirl 11/17/2011 07:42 PM

5 Attachment(s)
Asterina star and pyramid snail
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Nerite snail eggs
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Serpulid feather dusters
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Mini brittle starfish
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SushiGirl 11/17/2011 07:45 PM

5 Attachment(s)
Colonial tunicate
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Vermetid snails
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daplatapus 11/17/2011 08:40 PM

Wow! I just found out what at least a half a dozen things are in my tank that I just couldn't get a pic of. Thanks!
And Sushigirl, your tank much be a veritable cornucopia of little critters :D

SushiGirl 11/17/2011 09:01 PM

That was my old tank from years ago. And the camera I had back then was better at macro shots LOL.

evilvelle 11/17/2011 10:43 PM

Man there are so many pests out there.Wish I could do it all over again with dry dead rock and QT everything. I would love to use the rock I have in my display on a bigger tank in the future but I know I have some unwanted hitchhikers is there a way to dip or clean the rocks of pests and still keep it live with all the beautiful coraline algae?

WetShepherd 11/17/2011 11:19 PM


Originally Posted by evilvelle (Post 19528705) there a way to dip or clean the rocks of pests and still keep it live with all the beautiful coraline algae?

It's not the smartest thing I've ever done, but to get rid of the last few of my hitchhiking crabs (the ones so stubborn they wouldn't come out for even fresh water dips) I placed the pieces of LR that I suspected of having crabs into a bucket, then poured club soda through the holes/caves. The crabs got out in a big damn hurry.

It sounds extreme, but I suffered no discernible fallout for my ridiculous actions. I still have plenty of creepies and there was no increase in nitrates (i've never had ammonia). Before going crazy though, you could try an hour or two in a bucket without water with the lights off, or a short fresh water dip to see what you get.

All that being said, the time we spend with our live rock during the cycling process feels like a rite of passage. It's also a lot of fun. Maybe it gets old after you've set up several aquariums, but I think everyone in the hobby should go through those ups and downs at least once ;)

Here's the pic of my suspected eunicid - the pic isn't as good as sushi's (thanks so much for posting those!) but I think it's safe to call it a positive ID? Just above where the pics cuts off I have two colonies of Zoas :angryfire:

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