beautiful but can be deadly---think twice before buying: FYI

[Sk8r]

There are some creatures a lot of new hobbyists want---that have real problems with their tankmates. A short list, and others may add their own experiences.

1. coral banded shrimp: they're not cleaners. They eat fish. When small, they may be amusing. When they get larger, they make off with little Nemo or other fishes they can catch. Clowns, gobies, blennies, all sorts of fish that sit still are prey for them.

2. cucumbers, sea apples, etc---big fleshy inverts. Really neat, interesting creatures. BUT---a new tank tends to be chemically unstable, a life-threatening condition for these creatures. If cucumbers die, or are attacked, they release a toxin that is particularly bad in a new tank. Carbon helps, but may not be enough. Sea apples go to nasty slime when they die, and just release more 'stuff' than a new tank can cope with. Leave sea apples in the ocean: they're really not apt for tanks.

3. sally lightfoot crabs---I love them: they're splendidly amusing. But they grow the size of dinnerplates, and start eating your fish, and they are darned near uncatchable. You'll have to take your tank apart to get it.

4. chromis. People think these bright blue fish are going to be a cloud of neatly schooling bright fun. But they're damsels, highly territorial, generally school only when threatened by something meaner, and they have a nasty habit of all picking on the weakest of their pack, killing that one, then turning on the next weakest until they have reduced their numbers to a number (usually odd, 1, 3, 5, etc) THEY feel is ok for the tank size. One chromis is fun. Three are fun in a 75; maybe 5 in a 100g. BUt don't get them more friends. They eat them.

5. Damsels: a damsel (see chromis) is a bright, cheap, wonderful fish, but it needs a HUGE territory or it will pick on other fish. If you have a 100 g tank you can support 4-5 different species and get a lot of color. If you're smaller, avoid damsels. In a big tank, there's a lot of chasing, but very little to no nipping, so if you dont' mind the continual agitation, not a bad choice.

6. Elephant ear mushrooms. This is a hairy mushroom, usually brownish, kind of shaggy, that has a faster 'close' response than most: and they get huge. If you have one, you will notice your perching or sleeping fish disappearing one at a time. This mushroom will fold up around a hapless fish at night, make a bag of itself, and suffocate your fish. Which will be disposed of by the cleanup crew by morning, so you won't know what happened.

7. arrow crabs. Fascinating. But they will gobble up all your bristleworms, and a tank needs bristleworms far more than it needs a big pushy crab. The bigger they get, the nippier they get. Not as bad as a CB shrimp or sally lightfoot, but ultimately a problem that will deplete your reef of every other small unshelled species it can catch, lowering your biodiversity and weakening your cuc.

If you do have a non-poisonous creature that just bothers things, the sump/refugium can be a nice place to keep him. Big crabs, etc. If potentially toxic, your tank just doesn't need it.

[fstar25]

Sk8r,

Great post, thanks for all the info.

[seattlerob]

I put 2 sally lightfoots in my new tank and quickly realized they were a bad idea as I caught them picking at my corals.

I was able to get them out pretty easily though. I put a 16 oz drinking glass in the tank near the edge of a rock, and then some pellet food in the bottom of the glass. The fish would want to get the food, but too freaked out to go inside the glass. Eventually, the sally lightfoot would drop into the glass to get the food and then be unable to get out. I could remove him the next day.

HTH,

Rob

[brubinfeld]

i would disagree on a tiger cucumber as this animal is pretty hardy and the benefit outweights the risk, as long as proper care is taken

[Aimiel]

Wish I'd read this years ago. I bought three Blue Damsels, which I've had since I started my tank, over two years ago. They were fine, only chasing and never nipping anyone, until I got my Powder Blue Tang, about three months ago. To be sure he got plenty to eat, I overfed somewhat, which triggered the Damsels to mate. Once the eggs were laid, the male protected them like he expected every fish in the tank to just move out of 'his tank.' When the Powder Blue Tang began to show signs of stress, and couldn't get away from the Damsel (they're VERY fast fish) I decided they had to go. A friend took them for his aggressive tank, since they're just about the only fish than can elude his eel; and they're doing fine. He also took my Coral Banded shrimp, because it had eaten my Peppermint shrimp. =(

[Sk8r]

the tiger-tail, small size, is what's often sold in cuc's, and they can be an amusing species. Just remember that you have a somewhat more-fragile-than-some creature that does release a toxin if killed, and that the most frequent killer is water quality. Just be advised and aggressively stabilize your water quality, and nothing else in your tank will be unhappy about that, either. SHOULD you have a potential issue, run carbon asap, and change it out after 3 days, run more carbon, whle doing a 20% water change.

[Sk8r]

Let me add two handle-with-care corals to the list: 1) the very attractive fiji yellow leather is nasty if it starts to die. If you have any doubts about its health, and you suspect it could be starting to die, get it immediately into a bucket or tank not connected to your system, where you can heal it up without letting the creature aggravate anything else. Run carbon on that little system, and just keep changing it. Leather corals get into snits and spit into the water, and some are nastier spitters than others, that can touch off every other leather in the tank. In the open ocean, this just kills off rivals. In a closed tank, it's a circular firing squad. The sovereign cure for coral wars is carbon. Lots of carbon. And isolation.

2) hydnophora, a stony, can be particularly aggressive. Give it PLENTY of room, and wear gloves. Torch coral can be nasty to other corals...but hydnophora is more so. Bubble can surprise you. A first time buyer of ANY lps stony coral should be aware that many species put out tentacles at night that can reach up to 6", making them bad neighbors. Arranging your tank where no aggressive coral can get at another involves: space, prevailing current, rock barriers, and creativity.

[ctrl+f]

Argh, the more I read the more conflicting information I seem to collect.

A lot of sites recommend sally lightfoots and damsels as good beginner choices. A lot also consider bristleworms a pest to be removed--I've seen bristleworm traps for sure.

Is this just a matter of personal experience, or changing research, or what?

[jason2459]

Originally Posted by ctrl+f

Argh, the more I read the more conflicting information I seem to collect.

A lot of sites recommend sally lightfoots and damsels as good beginner choices. A lot also consider bristleworms a pest to be removed--I've seen bristleworm traps for sure.

Is this just a matter of personal experience, or changing research, or what?

I believe they are sold as a good beginner fish and crab because they are very hardy, cheap, and very easy to take care of. For a beginner that is good to help increase their confidence and hope that they stay in the hobby. Which is all good. So, after you are successful with those then you find out how terrible they are when you start trying to add anything else.

I believe bristleworms get a bad wrap because they are ugly and can get pretty big. Plus they can hurt like heck if you get pricked.

Edit: BTW, great thread Sk8r

[jason2459]

You might also want to mention about that really pretty looking grouper that you often see will get HUGE and eat everything. This also goes along with most items. Just because you see it in a small 10g display tank doesn't mean it will survive there or stay that small...

[Tomaric]

Nice post, cuddo's to u.

[Sk8r]

Bristleworm traps are an anachronism, really. When bristleworms first started turning up in the hobby, almost always at the scene of a death in the tank, people assumed they were responsible for the demise and that they would be death on everything---well, they were innocent. They're not serial killers: they're undertakers, and they come to where things have died of other causes. Now some researchers suggest they may even be essential or highly helpful to sps coral growth, predigesting food into sizes coral mouths can take in. At very least, they're beneficial CUC, who will save your tank if you have something nasty decay somewhere you can't reach. They'll take it out within 24 hours and convert it to niceness for corals. Big ones aren't a problem until they top a foot and a half in length, and then only because they're a big biomass. They come in many species, but the legendary fireworm has never been demonstrated in my experience, and I regularly keep (and am amused by) the big pink ones, which regularly get about a foot long, keep to a single hole in one rock and only reach out for spare fishfood. The main get-it-out worm is the eunice, which looks like a centipede with tentacles on its head. It's not a bristleworm, and can become a pest: if you do get it out, just drop it into your sump, where it can live a useful life.

The other two are recommended because they're hard to kill. "Hard to kill" is a dubious recommendation, and personally, I'd rather tell you to keep your water at the marks I have in my sig and then you can get beyond the 'hard to kill' species. Here's the problem with them: Most beginners don't have big enough tanks for damsels, and while sallies are charming while small, they're a PITA when they succeed and grow. {a real 'hard to kill' tank would be a 100 g tank with: lots of aiptasia, brown mushrooms, bristleworms, button zoas, yellow star and green polyps, several species of damsels, cerith snails, and a sally. ]I have to scrape green polyps off my glass oftener than I do coralline!] Actually the tank would look kind of neat, in a wild, brown and green sort of way, would ramble on for years looking much the same, and it would certainly be a minimum care tank!]

As a rule, do not allow any pancake-shaped crab but an emerald mithrax into your tank. As a second rule, "big claws, big trouble." Little tiny coral-crabs are usually fine, ditto the decorators, and the micro-hermits like scarlets, micro-bluelegs, (neither of these bother snails) and there's another nice one with black legs and white joints. The scarlets are my personal favorite, lively and great comedians---everything you love about the sally, but none of the downside.

[Elysia]

Originally Posted by Sk8r

As a rule, do not allow any pancake-shaped crab but an emerald mithrax into your tank. As a second rule, "big claws, big trouble."

Except that rules have exceptions... The non-anemone associated porcelain crabs are "pancake" shaped and have huge claws, but they are harmless to all, beautiful, and interesting.

[Sk8r]

Yep. The porcelains are really gorgeous and interesting creatures. And good citizens, so far as I know. A more universal rule is 'no hairy crab'---but that still lets people buy sallies. You can also say: if a crab lives in a coral or nem, it's probably commensal (sharing the food of the creature it lives with) and therefore not a problem. If it's living in the rock, it's got to go hunt something to eat, and you need to know what it's eating. The ocean is full of surprises, and so will your live rock be---particularly if you don't 'cure' it {a practice I don't like for myself.] And---alas---it's not always a case of commensality: it's also a rule that things travel with what they eat. So if you find a pretty little hitchhiker slug, say, in your coral---id it! Zoas in particular bring in a lot of sea slugs that are travelling with their lunch. Ie---they love to eat zoas.

If you do get one of the exotic crabs or other weird creatures of the ocean as a hitchhiker, ask before taking it out; it's not going to eat anything in the time it would take to consult about it. And to catch a crab, if you can lift out the rock it's in and drop that rock in a nice bucket, you have got the crab.

My rule is: if I don't trust it, I still don't kill it. It goes to the refugium Many tiny, tiny species can get through the pump back to the tank---but larger organisms are generally safe unless their young can make it through the Cuisinart of the pump. I'd recommend if you can catch it without damage, catch it, photograph it, id it with the help of RC, and THEN decide whether it's back into the tank or into the fuge.

[ctrl+f]

That was a very useful followup, thank you.

[DirtyDeeds]

ty for the great post

[Sk8r]

And you will find inappropriate species offered for sale in the pet market. Somebody asked why we don't keep tuna. Max speed of a tuna in the wild is clocked at 40-60 mph AND UP, so that sort of tells you why we don't keep some species. The panther grouper is gorgeous and fun to watch---but a grouper grows LARGE, and eats anything that fits in his mouth. Groupers get so big they approach divers with no fear, being about the size of a car engine. Jacks are too large for a home tank. Yet they sell them. It is NOT true that a fish only grows to fit its tank. Fish grow to fit their food and oxygen supply, and if they can't move or aerate adequately, they decline and die, a cruel fate. So while we're not talking, in this comment, about species actually dangerous to your tank, they're certainly inappropriate.