Your Cleanup Crew, inverts, and You... FYI

Sk8r

Staff member
RC Mod
When you've just cycled, very likely you don't have enough food for the size CUCs most sellers offer. Most will starve.

Instead---get a couple of snails---ceriths are good---and watch their behavior. Or a couple of micro-hermits, the sort that never get a significantly large claw, never grow larger than a snail shell will accommodate. And when you get crabs, get a fistfull of shells JUST LIKE the shell they're wearing, only larger, if you can. It's only humane. And little crabs are fussy: most pick only one type of shell, ever. If you're very lucky you may have acquired a strange snail from your live rock: the stomatella---long antennae, only a hard 'saddle' for a shell, and move fast. Real nice snail! You almost never see them for sale. You may also accidentally acquire limpets (round cone with hole in top, very small) and chitons (kind of a skeleton like a sowbug, often with a black 'cape that covers most of it: they're nocturnal and hate light, so it's rare you'll see them. Never try to move one: you'll hurt it. Abalones are also good.

Watch their behavior until you're sure they're happy and ok.

Then you can, every week for the 4 weeks your first fish spends in qt, get a few more. Get ceriths, mostly. Turbos sound nice, but they're not adapted to sand beds and frequently get out on the sand, fall over, and helplessly starve to death if a crab doesn't decide they're fair game that way...they're kind of like vultures, and won't turn down a dying meal. Bristleworms are good. Most kind of worms are good, and if you're lucky they came in your rock---just don't handle them without gloves, or their spines will make your fingers unhappy. Sponges are good, but don't buy one. Your tank may have 'wild' ones, but you're not really stable enough yet.

You are not stable enough for an anemone and won't be for most of a year. You COULD get a few discosoma mushrooms. But you can wait.

Go on increasing the crew for your four weeks. All ceriths, if you can manage it. Scarlet hermits are good. Hardy, long-lived.

After you have had fish for 2 months in the tank. You will need 2 large nassarius per 20 gallons. Or quite a few smaller ones. They live under the sand. You can get one fighting conch per 50 gallons, no smaller tank. These creatures maintain your sandbed.

Do not get a sand-sifting goby or an anemone until your tank has been up and running well for a few months. The goby will starve. The anemone may not settle and could kill the tank.

Avoid arrow crabs: they do in your bristleworms and contribute nothing useful.
Avoid cucumbers and starfish (except the brittle stars: they're good) Avoid the green serpent star, which is a fish predator. Otherwise the cucumbers are going to starve and the starfish won't be safe with any corals and will probably starve after a month. Avoid margarita snails---pretty, but will die quickly in warm water. Avoid coral banded shrimp: they may take after your fish. Avoid cleaner shrimp in a tank under 75 gallons...they can pick on your fish. Peppermint shrimp, however, eat aiptasia---at least some do. Not all. Hit and miss.

Confine your CUC to worms, cerith snails, micro-hermits like the scarlet. And increase their numbers slowly. Ceriths will breed in your tank. Crabs--alas, their young don't survive. If you like, you can get an urchin, late in the 4 weeks: the pincushion urchin does the least rock-pushing

I will add one snail that is my favorite: variously called the dove snail or the conch-shaped miniature strombus grazer, related to the conch, I think, but about a third of an inch long. These tiny snails get where others can't and clean like bandits. They never fall over---they spin a spidersilk line to get from one rock to another, and they multiply like bandits.
They also are of a size to get into places like the inside of your pump, but it rarely happens. If you do have a pump not working the way it did once, disassemble, extract snail, reassemble, piece of cake. Not a big enough nuisance for me to give up these prolific little fellows. If your fish store has them, they'll often just give them to a good customer. At very least, they're cheap. ;)

Hitchhikers like hairy crabs, or smooth crabs with a distinct largish claw, are not good. Neither are worms with tentacles on their heads. Nor are clicking sounds from your tank, which indicates a pistol shrimp or worse, a mantis shrimp. Either shrimp is great in a dedicated mantis tank, but they kill fish. And I include the happy little pistols sold as pairs with gobies---my tiger grew large, prosperous, killed his goby partner, then took out several firefish and a mandarin before I took my tank apart to catch a stupid half-inch shrimp.

If you find anything else---ask. If it's watery, most of us have been there, done that, and can tell you, eg, that scallops will die, and rescuing a grocery store oyster will not end well. So also with more exotic creatures that turn up on sale.
 
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Thanks for that info. I recently found a little red "acro" crab, as was ID'd by a few fellow refers. It looked like a red emerald crab, no hair. They said he was harmless... WRONG! I got up in the middle of the night and caught him red handed with a zoa in his claw. Next morning when he was back in his hole in a rock, he somehow got entombed with super glue...lol! No more crab. My medium hermits are also becoming more bothersome, stealing food from my corals when I target feed. So, I have learned smaller crabs are better. For some reason I have never had much algae in my tank, despite a phos level of .25 and nitrates 40-60, except coralline algae. I am glad, but I wonder why?
 
Crab thefts from corals are usually a minor issue, since most corals get all they need from light or from dissolved elements in water, but the lack of algae is rather curious with those readings...
 
Yes, it's strange. I have NEVER had an algae breakout, even when my tank was cycling. Thanks for the post!
 
Lol---
Re your crab making off with a zoa---any crab with a claw big enough to run off with a zoa has claws that make him an Unfriendly.

Also beware of sally lightfoots, a very amusing crab that's quite agile and hard to catch---great in the sump, but when you realize they grow to considerable size, as in half a foot across, they're not so good. Crabs are kind of omnivorous: they'll eat carrion, other inverts, algaes, and fish---their bill of fare changing as they grow and get more able.
 
Ha ha, jinxed myself! I hope not! I think the only crabs I have now are the ones I purchased. I'm super careful about what is in my tank. Sometimes you can't help what shows up, but not always bad. I have a nice urchin that was a hitchhiker, now about the size of a ping pong ball!
 
Useless and occasionally take a nip out of fish fins, but kind of entertaining.
 
Sk8r - I hope to have my tank up and running this week. I've been cycling rock in a couple bins from Lowes since for two months now. Ammonia and nitrites are at zero.

I hope to head over to a somewhat LFS this weekend to pick up some actual live rock - I'm intrigued by the idea of the diversity it will bring. I think it makes sense to also buy the beginnings of my CUC.

The tank is 120g with a 40Br sump. Do I literally start with just 2 ceriths? Also, should I QT them? If so, should I get more and slowly move them from the QT to the DT over several weeks? The LFS is about 75 minutes each way...

Thanks!
 
If the inverts you buy have been housed in any tank that shares a sump with a fish tank, or that has fish in it, a 72 day quarantine is warranted. The problem is either snagging ich 'swimming form' in the water, or having the 'encysted form' somehow attached to the shell. Know your sources. And if you have any doubt, don't be shy about asking the seller. Tell them it's for purposes of quarantine, not that you'll refuse to buy. Same with asking them about their salinity for a particular purchase. It's need-to-know kind of info that affects how you treat the specimens when you get them.
 
Sk8r - does buying snails from a reef only tank go by the same measure? Like my LFS in my area only sell their snails in Reef frag tanks.
 
Thanks!

If you were me, how many snails would you buy?

Sounds like I will need to QT them. If that's the case, shouldn't I buy more than 2?
 
Just a little warning on the urchins - they love to pick stuff up to use as camoflage. That could mean rocks, pieces of shells, whole shells. Anything they can find. That also means any frags that aren't glued down. Nothing like finding that nice new frag you just stuck in a hole in your rock face down on the sandbed because the urchin found something else to play with.

And they'll pick up those little micro hermits. More than once I've picked one of those little guys off the back of my urchins. It doesn't hurt them, so I suppose it's no harm no foul, but it's kind of sad to see them helplessly stranded atop another member of your CUC.
 
If you must qt them, get your whole CUC and just add them slowly. They can live in your qt as you qt fish: 72 days each fish, and you move them and a few more inverts in.

Yep: urchins are rock-movers. If you have a lot of delicate balancing, Reef Putty can help. Or have no urchins.
 
This thread couldn't have been posted at a more perfect time for me. I'm ready to add a CUC and have been reading for some time how to go about it. I've copied and pasted this into a word doc. Thanks again for another great "Ask Sk8r" advice column. ;)
 
What about emerald crabs?

My very large male just found his way to the sump, in a not so pleasant way :blown: :hammer: he decided to eat my two peppermint shrimp and not one but two royal grammas. They were very tiny but still... I'll be getting a replacement royal gramma tomorrow :thumbsup:
 
thx

thx

thx for the extended rundown, i need to get my CUC started, ill see what my LFS has in stock this weekend, but ive got some...bubble algae? I guess it is, idk where it came from, this only my second salty tank and the other never had any in it, and the only livestock i have came from that tank lol, unless diatoms can do the bubble thing too if they have enough light.

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What do i feed my CUC while QT'ed? I added some nassarius snails without QT...then ich, live and learn, lost my Coral Beauty in my avatar, and my royal gramma, my other 4 fish pulled through, but they were rough looking, but the tank ill be QT'ing the CUC in is the one that had ich, it is fishless atm, but might as well use it as it is still up and running with its previous spineless inhabitants in timeout.
 
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Hi Sk8r,
I am planning on introducing 2 cleaner shrimp and 2 peppermint shrimp to my 55gallon tank. My tank is a bit over two months old. Is adding cleaner shrimp a bad idea?
 
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