Difficult and Special Care Species List

Peter Eichler

New member
Fish To Be Avoided::Fish that have incredibly low survivability in aquaria or are totally unsuitable for home aquaria


Moorish Idol (Zanclus cornutus): A few success stories, but miniscule amounts live long, difficult feeder, mystery deaths, and even when accepting prepared foods often slowly starve

Rock Beauty Angelfish (Holacanthus tricolor): Nearly impossible to meet the dietary needs in home aquaria

Multi-Barred Angelfish (Centropyge multifasciatus): They don't adapt to aquarium life well, rarely eat, and are very secretive, though not fatal, they also seem particularly prone to Lymphocystis

Venustus Angelfish (Centropyge venustus): See the Multi-Barred Angelfish above

Butterflyfishes (Chaetodon spp.): Many problem feeders in the group and most are corallivore that are almost guaranteed to starve to death in aquaria, do a lot of research before purchasing any butterflyfish

Clown Tang (Acanthurus lineatus): VERY ich prone and a finicky eater, horrible survival rates, when they do live they are terribly aggressive and often take over a tank

Twinspot Goby (Signogobius ocellatus): Terrible survival rates in captivity, rarely accept prepared foods or survive long even when they do

Clown Sweetlips (Plectorhinchus chaetodonoides): Difficult feeders and rarely adapt to aquarium life, should you manage to get one to live they get quite large

Oriental Sweetlips (Plectorhinchus orientalis): See Clown Sweetlips, in general this can be repeated for most species in the genus Diagramma and Plectorhinchus

Pinnatus Batfish (Platax pinnatus): Gorgeous fish when young, very very few success stories, diet, disease, and stress from aquarium life are big issues

Tiger Tiera Batfish (Platax batavianus): See Pinnatus Batfish above

Orange Spotted Filefish (Oxymonacanthus longirostris): Specialized coral polyp feeder and almost never accepts prepared foods

Ribbon Eel (Rhinomuraena quaesita): Rarely eat in captivity and are excellent escape artists

Snake Eels & Garden Eels (various genera): Difficult feeders that require specialty tanks

Cleaner Wrasses (Labroides spp.): Specialized parasite feeders that rarely live long in captivity, leave them in the ocean where they can do their job

Tamarin Wrasses (Anampses spp.): Very poor shippers and need tanks with their special needs in mind, even then they often starve to death, their best chance is often a large established reef aquarium with large amounts of live rock, peaceful fish, and something to prevent their escape from jumping

Leopard Wrasses (Macropharyngodon spp.): See Tamarin Wrasses above, but there are more success stories, both these and the Anampses are boderline being in this area of the list and the next section

Pencil Wrasses (Pseodojuloides spp.): Very sensitive, they almost always die in transit so you don't see them very often if ever in the trade

Parrotfishes (Family Scaridae): Very specialized feeders on mostly dead (some live) coral skeletons and the algae and organisms associated with them, they adapt poorly to aquarium life in almost all regards

Tilefishes (Family Malacanthidae): VERY timid and must be kept in a covered aquarium with lots of space and docile tankmates, in general they just don't adapt to aquarium life

Cartilaginous Fishes (Sharks, Rays, Skates): With very few exceptions, unless you own a massive aquarium that is several hundred gallons stay away

Grunts (Family Haemulidae): Rarely adapt well to aquarium life and should probably only be considered in a large species tank

Jacks (Family Carangidae): See Grunts above

Drums (Family Sciaenidae): Poor shippers, being very shy and fragile they rarely live long after being collected

Trumpetfish (Aulostomus spp.): Too large and too specialized for 99.9% of the aquarists out there, also poor shippers

Remoras (Family Echeneidae): Unless you have a large Shark or Whale in your backyard oceanarium it's probably best to stay away

Leopard Blenny (Exallias brevis): Specialized coral feeders that rarely live long in captivity

Chambered Nautilus (Nautilus pompilius): Though technically not a fish, there are a plethora of reasons to leave them in the ocean, simply not suited for typical aquarium life







Fish Best Left For Experienced Or Knowledgable Hobbyists:Finicky nature, parasite prone, specialty feeders, require specialty tanks, or threatened species


Anthias (family Anthiinae): Require a good amount of swimming room, peaceful tankmates, and frequent feedings, often unhealthy and starving by the time they make it to dealers tanks, some almost require special tanks with their needs in mind and others often refuse to eat and starve quickly in aquaria, do plenty of research before purchasing any Anthias

Teira Batfish (Platax teira): Can be very hardy once acclimated but there can be problems feeding, they stress easily, are disease prone, and will also outgrow most aquaria

Majestic, Blueface(Pomacanthus Euxiphipops spp.): Can be hardy once acclimated to aquarium life and eating well, that's often easier said than done though, larger juvenilles are often the best way to go with these fish as tiny specimens are quite fragile and large specimens have the hardest time adapting to aquarium life, this is true for many large angelfish

Regal Angelfish (Pygoplites diacanthus): A problem feeder, specimens from the Philippines and Indonesia rarely make it long in captivity, Red Sea Specimens tend to be hardier and more willing to accept prepared foods partially due to collection and holding techniques, the more recent trend to keep this fish in reef aquariums helps with survivability

Bandit Angelfish (Holacanthus arcuatus aka Apolemichthys arcuatus): Very similar to the Rock Beauty above but with a much smaller sample, at their price you'll probably do your research, if you don't you'll most likely learn an expensive lesson

Bicolor Angelfish (Centropyge bicolor): Concerns with drugs used in collection and frequent unwillingness to accept prepared foods, also one of the more common coral nippers

Heralds's or Yellow Angelfish (Centropyge heraldi): Often collected with the use of drugs, be very wary of newly collected specimens, this can be true with many Centropyge but seems especially problematic here

Lemonpeel Angelfish (Centropyge flavissima): See Herald's angelfish above

Potter's Angelfish (Centropyge potteri): Mixed results with this one with a lot of mystery deaths early in captivity, if they've been eating and active at the fish store for a few weeks they usually end up being quite hardy

Golden Pygmy Angelfish (Centropyge aurantius): Adapts poorly to aquarium life, only attempt if you find a healthy specimen and have a larger reef aquarium containing less boisterous fish with a lot of rock to graze on

Swallowtail Angelfishes (Genicanthus spp.): Can be hardy once acclimated, but lots of problem specimens due to the depths they are collected at, take extra special care in examining and observing them before purchase

Angelfish in General (Centropyge, Chaetodontoplus, Apolemichthys, etc. spp.): Just a general note, Angelfish are among the more common fish collected using cyanide, so paying particularly close attention to their behavior and appearance before purchase is advised

Butterflyfishes (Chaetodon spp.): Very few are suited for a reef tank or a beginner hobbyist, do your research

Copperband Butterflyfish (Chelmon rostratus): Like the Regal Angelfish, this one has gone from nearly impossible to having some success with the popularity of them being kept in reef tanks, even then, longevity is questionable

Garibaldi Damselfish (Hypsypops rubicunda): Typically will not do well longterm in tropical conditions, if they do live long that cute little fish turns into a large territotial nightmare

Trunkfish, Boxfish, and Cowfish (various genera): Most are rather sensitive and can release toxins when stressed or dying

Clown/Gumdrop Gobies (Gobiodon spp.): Poor shipper, once established can be a good surviver with less boisterous fish, will nip "SPS" corals

Catalina gobies (Lythrypnus dalli): Not a tropical species and will not live long in the temperature of the average marine aquarium

Mandarin "Gobies" and Scooter "Blennies" aka Dragonets (family Callionymidae): Require large amounts of live food, quite often starve to death, providing larger tanks (50+ gallons) with large amounts of live rock and little competition for food has proved successful, do not treat with copper medications

Radiata Lionfish (Pterois radiata): Tough to acclimate to aquarium life and foods, more sensitive than others in the genus

Fu manchu Lionfish & Dwarf Zebra Lionfish (Dendrochirus spp.): All the dwarf Lions require tanks with their needs in mind, these two also seem very sensitive, very shy, are poor shippers, and can be particularly difficult to ween onto aquarium foods

Anglerfishes and Frogfishes (Order Lophiiformes/Antennariiformes): Most get very large and can consume fish nearly their own size, often will only consume live foods which is troublesome since feeder fish are rarely nutritious enough longtern

Achilles, Powder Brown, Powder Blue, and Gold Rim Tangs (Acanthurus spp.): Ich prone and fairly sensitive to water conditions, they also require large amounts of swimming room, very risky to consider one without quarantine

Bristletooth Tangs (Ctenochaetus spp.): Ich prone, some of the hardier tangs once established but can starve when detritus and algae aren't available in decent supply, so overly "clean" aquariums are not a good choice, the Chevron is probably the least hardy of the genus and can be particularly difficult

Seahorses, Seadragons, Pipefish (Family Syngnathidae): Need quiet species tanks and large quantities of nutritious live food, wild caught specimens ship poorly and have high mortality rates, tank raised seahorses are often already accepting prepared foods and are much better candidates for aquarium life, they still need a tank with their needs in mind though

Hawkfishes ( Family Cirrhitidae): Hardy fish but they are notorious jumpers, be very careful with ornamental shrimp, crabs, and small fish

Porcupine Pufferfish (Family Diodontidae): Can be hardy but some are very disease and parasite prone, most require large fish only aquariums

Fairy and Flasher Wrasses (Paracheilinus and Cirrilabrus spp.): Require peaceful tankmates and do best in reef aquariums, they stress easily and the first few weeks in captivity will often make or break their longevity, known jumpers

Lawnmower Blenny (Salarias fasciatus): Will sometimes not accept prepared foods and will starve to death in tanks without a natural algae food source

Diamond, Golden Head, Sleeper Gobies (Valenciennea spp.): Sometimes starve to death even when accepting prepared foods, tanks with large sandbeds containing lots of food will help as will frequent feedings when they will eat, mated pairs may help as well

Courtjester/Rainford's and Hector's Goby (Amblygobius spp.): Often will not accept prepared foods, need established tanks with a fine sandbed full of life

Fourline Cleaner Wrasse (Larabicus quadrilineatus): A cleaner when small, but are coralivores as they enter adulthood so are not good reef aquarium inhabitants, some of the Tubelip Wrasses are know for a similar behavior and rarely live long in captivity

Cephalopods, Octopi, Cuttlefish, Squid (Class Cephalopoda): Not fish, but including them here because of their intelligence compared to the dumb lumps of goo that are most invertebrates, the Nautilus from above is in this group as well, these must have species tanks and require a lot of research before attempting them







Fish That Require Huge Aquariums (200 gallons or more):


Cartilaginous Fishes (Sharks, Rays, Skates): Require tanks much larger than 200 gal. and should just be left out of home aquaria, Nurse sharks can grow to 14ft. long!, repeating this one so it sinks in

Groupers & Seabass (various genera): Especially take note of the cute little Panther Groupers commonly offered in the trade as they can attain over 2' in length

Snappers (Family Lutjanidae): Those little Red Emperor Snappers seen in the trade get over 3' long

Unicorn Tangs (Naso spp.): They will even outgrow common size aquariums such as 125 gal. and 180 gal.

Moray Eels (Family Muraenidae): Do your research as many are not suitable for home aquariums

Squirrel and Soldierfish (Family Holocentridae): Some of these are borderline, do your research

Batfish and Spadefish (Family Ephippidae): Probably best left to public aquaria

Twinspot Wrasse (Coris aygula): Take special note of this one as they're often offered as small attractive juveniles, they get very large and very mean, up to 4' long

Red Coris Wrasse (Coris gaimard & Coris frerei): Sold as tiny juvenilles they can grow up to be 2' beasts, beware the size of most Coris wrasses, though the common Yellow Coris Wrasse is actually a smaller fish from not in the genus Coris but belonging to the genus Halichoeres

Dragon Wrasse (Novaculichthys taeniourus): Offered as very small juvenilles they grow to be about a foot long and are known to flip aquarium decorations and rocks when adults

Flounder (Paralichthys spp.): Rarely suitable for aquarium life, also becoming increasingly rare due to overfishing as a food fish

Tassled filefish (Chaetoderma pencilligera): Often offered when cute and tiny but grow quite large

Angelfish (various genera): When purchasing any angelfish that isn't Centropyge be sure to check their ultimate size, take special note of the French, Gray, Blue, and Queen which are often offered as small juvenilles ang will outgrow most aquariums

Triggerfish (various genera): Most will be fine in large aquariums of around 100 gallons, but there are a few that would be unsuitable for all but the largest home aquariums, do research on their ultimate size and temprament before a purchase is made







Venomous and/or Toxic Species:


Stonefishes (Synanceia spp.): Believed to be the most venomous fish in the world

Scorpionfishes/Rockfishes (various genera): Rhinopias has gained in popularity recently

Toadfish (family Batrachoididae)

Lionfish (various genera)

Rabbitfishes/Foxfaces (Siganus and a sub-genus Lo)

Coral Catfish (Plotosus lineatus): These also get up to a foot long and become more solitary as they grow

Blue Ring Octopus (Hapalochlaena spp.)

Fang Blennies (Meiacanthus spp.): Venomous bites that can be painful

Flower Urchins (Toxopneustes pileolus): Rare in the trade, but outside the trade there are reported deaths from this species

Black Longspined Sea Urchins (Diadema spp.): Can inflict painful wounds, some debate exists whether or not they are really venomous, but it's wise to handle all urchins with care

Cone Shells (Conus spp.): Rarely encountered in the aquarium trade, can be deadly

Stingrays (familly Dasyatidae): Many have venom associated with the spike on the tail which they use in self defense, fatalities are very rare

Sea Snakes (various genera:) I know you're not going to try to add one to your reef aquarium, but included for good measure

Box Jellyfish (Chironex fleckeri): Quite deadly but of no concern to aquarists

Hell's Fire Anemone (family Actinodendronidae): While all anemones are capable of stinging, this is the one of the few to be concerned about, very painful stings

Hydroids: usually just cause skin irritation if anything

Fire Coral (Millepora spp.): See hydroids

Sea Mat, Button Polyps, Zoanthids (family Zoanthidae): Some of these can contain Palytoxin which can be quite dangerous, they're quite frequently harmless but if you want to err on the side of caution rubber gloves are a good idea when handling them, as are goggles when fragging them







Extremely Aggressive Species:


Undulated Triggerfish (Balistapus undulatus): Perhaps the meanest aquarium fish available and one to avoid unless you don't mind having a large aquarium with one fish

Queen Triggerfish (Balistes vetula): Not quite as bad as the Undulated, but pretty close and what they lack by comparison in aggression they more than make up for in size

Clown Triggerfish (Balistoides conspicillum): Pretty similar in demeanor to the above two

Blueline Triggerfish (Pseudobalistes fuscus): Not so bad when young, but a beast once it grows, probably the least aggressive of the four triggers mentioned

Passer Angelfish (Holacanthus passer): Probably the meanest of all Angelfish, some of the larger Angels may look like delicate beauties, but some can be quite aggressive

Damselfish (family Pomacentridae): They're not all bad, but ounce for ounce some of them are the meanest fish around, think long and hard about adding them as some of your first specimens

Maroon Clownfish (Premnas biaculeatus): Females get quite large and they can take over medium size tanks, they're also probably the least tolerant of other clown species

Sohal Tang (Acanthurus sohal): Much hardier than the Clown Tang but just about as mean, probably best to keep them as the lone Tang, and if you must keep one in a community reef tank make it your last fish addition

Bicolor Pseudochromis (Pseudochromis paccagnellae) A lot of Pseudochromis get a bad wrap, but this isn't one of those cases, very nasty fish, P. porphyreus, P. diadema, and P. aldabraensis are others to be weary of







Inverts To Be Avoided Or Better Left To Experts:


Non-photosynyhetic Corals and Gorgonids (Sun polyps, Carnation, Devils Hand, Chili Coral, etc.): If it's a soft coral and not green or brown in part and is very vividly colored odds are it's non-photosynthetic and requires more small particles of food than most aquarists are willing or able to provide.

Christmas Tree Worms (Spirobranchus spp.): Filters feeders that rarely live long in home aquaria

Coco Worms (Protula bispiralis): See above

Flowerpot Coral (Goniopora spp.): Some progress has been made, but still miserably low survival rates and mopst are still doomed, stokesi is the most common and seems to be among the most difficult in the genus

Feather Starfish (Himerometra sp.): Require huge amounts of flow and large amounts of tiny planktonic organisms

Basket Starfish (Astrophyton muricatum): Similar to feather stars above, but even less suitable for typical aquarium life

Crown of Thorns Starfish (Acanthaster planci): Just seeing if you're still paying attention...

Linckia Starfish (Linckia spp.): Disease issues and shipping stress kill a large percentage, the ones that remain often slowly starve to death

Wild Acropora Corals (Acropora spp.): Wild colonies can be particularly adapted to flow and light from their natural environment and often do poorly once in aquaria, seek out hardier aquacultured specimens

Sea Apples (Pseudocolochirus spp.): Often slowly waste away if not offered large amounts of food appropriate for filter feeders, also a chance for toxins to be released and possibly kill other organisms

Margarita Snails (Margarites pupillus): From temperate waters and don't seem to adapt to warmer waters as well as some other clean up crew members from similar waters

Green Brittle Starfish (Ophioarachna incrassata): Can get large and boisterous, some reports of them actually ambushing unsuspecting or sleeping fish

Sea Pens (Order Pennatulacea): Terrible additions to home aquaria and are very short-lived

Sea Slugs and Nudibranchs (Subclass Opisthobranchia): Very specialized feeders, a couple can be useful to elimate pests but it is very difficult to sustain a food source for even those, they're also very prone to damage by overflows and pumps

Flame Scallop (Lima scabra): Filter feeders that usually waste away in home aquaria, the same goes for other scallops which are less frequently encountered in the trade

Anemones (various genera): Most anemones should be placed in specialty tanks and also have very poor survival rates, beginners should not attempt Anemones without extensive research
Bright Yellow Anemones (dyed; and done most commonly with Sebae, but also seen on occasion with long tentacle and carpet anemones

Harlequin/Clown Shrimp (Hymenocera picta): Must have live starfish to feed on to survive

Camel/Mechanical Shrimp (Rhynchocinetes durbanensis): Not reef safe but often sold as as such

Elegance Coral (Catalaphyllia jardinei): Recent poor survival possibly due to a disease, other factors might relate to them coming from higher nutrient environments

Pipe Organ Coral (Tubipora Musica): Often hacked off from a larger colony, recent survival seems better than in the past

"Decorative" Sponges (Porifera) Often hacked off from large colonies, also exposed to air for too long which often leads to their demise, bright orange and yellow colors are common

Horseshoe Crab (various genera Limulus polyphemus most common) Grow too large for home aquaria but will die of starvation long before they have the chance









Special Notes:


Clownfish (Amphiprion spp.): Various species often acclimate poorly to aquarium life and suffer greatly from collection stress, I've seen estimates that as little as five percent of those collected live to be in home aquaria, when possible buy tank raised specimens

Bangaii/Borneo Cardinals (Pterapogon kauderrni): Rather limited in range and rumors of an unsustainable population if the current rate of collection continues, there are also stories of poor survival after collection, buy tank raised when possible

Tangs (various genera) Should have larger aquaria to provide them with plenty of swimming room, no a tang is not suitable for your nano or 29 gallon tank, when small 3'-4' aquariums can be suitable for short periods of time or smaller species, though bigger is recommended by many

Angelfish (various genera): Their compatibility with corals and clams is often brought up and debated, outside of Geniacanthus there really is no such thing as a "reef safe" Angelfish and even those have the odd exception, before purchasing one consider how difficult one would be to catch out of your display tank after it decides your corals and favorite clam are delicious, they can be model citizens but there is always a risk associated in reef aquariums
 
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Great job, Peter. I am copying this to Reef Fishes as well and making it a "sticky" in that forum.
 
Chambered Nautilus

I have seen them in a public aquarium. The tank is not very large. I wonder how long they have lived there, or if they are just replaced when dead.
 
<a href=showthread.php?s=&postid=10293313#post10293313 target=_blank>Originally posted</a> by wooden_reefer
Chambered Nautilus

I have seen them in a public aquarium. The tank is not very large. I wonder how long they have lived there, or if they are just replaced when dead.

Last I heard only the Waikiki aquarium was properly suited to keeping them any length of time. You'd be shocked how often animals are/were replaced at public aquariums. I do believe it's far better now than it was 10-20 years ago though.
 
Hi Peter,

Great lists!...could I beg your permission to repost them on another reef forum I frequent?

thx
 
<a href=showthread.php?s=&postid=10294339#post10294339 target=_blank>Originally posted</a> by OmarD
Hi Peter,

Great lists!...could I beg your permission to repost them on another reef forum I frequent?

thx

Feel free :)
 
<a href=showthread.php?s=&postid=10291614#post10291614 target=_blank>Originally posted</a> by Peter Eichler


Centropyge heraldi (almost always caught using drugs)

I hope he isn't selling crack to my other fish!

Great list btw. Thanks for posting.
 
I have a zebra striped damsel fish that attacks any percs that I put in the tank--its been impossible to get it out of there. The LFS suggested I purchase a tomato clown and it would kick the damsels butt-------
I really don't like the idea of fish fights--that's not in the spirit of keeping a reef tank--besides with the damsel--he'd probably be lucky enough to win :)
Any suggestions
 
Thatnks for the info, an awesome list. It's really helped me out. I am just starting to setup my first saltwater tank. Thanks again.
 
I have printed this list off and take it with me to the LFS--just amazing at the misconceptions they like to flog time and time again.
 
<a href=showthread.php?s=&postid=10413934#post10413934 target=_blank>Originally posted</a> by KEstep
I hope he isn't selling crack to my other fish!

Great list btw. Thanks for posting.

LOL ok I've been laughing at this comment for 5 mins... my husband thinks I'm nuts :D
 
I had a blue hippo tang that killed a larger blue jawed triggerfish and a similar sized clown trigger.
 
Wow,

Is this common, i was planning on getting a blue jaw and i have a 5' bule hippo, my hippo is very shy though, should i avoid anyways?


<a href=showthread.php?s=&postid=10831007#post10831007 target=_blank>Originally posted</a> by roblack
I had a blue hippo tang that killed a larger blue jawed triggerfish and a similar sized clown trigger.
 
Great list, but I do have some comments on the AVOIDED animals list:

While I agree with any animal that we know the diet and can not provide, others could be tried until their conditions are understood and able to be provided, just look at what they used to say about keeping corals alive, it wasn't that long ago it was considered impossible to do.

I collect all of my own animals, I live in Florida and have family in Hawaii so I have experience with fish like rock beauty and moorish idols, with rock beauty it is a common deeper water fish and it doesn't handle drugs or rough handling. Most (not all) commercially collected rock beauties are caught using quinaldine and when brought up "poped". Quinaldine is a legal collecting drug in both Florida and Hawaii. I have 3 that I hand caught and decompressed that have lived together in a 70 gal tank for over 3 years. Most of the ones I have given to friends are still alive and once they take prepared foods seem to do well and grow (of the ones I have given to friends only 2 have died).

I also spend 3 weeks to 1 month a year collecting in HI and have done several experiments with moorish Idols. I collect 8, put 3 in my 55 gal tank (I have a relative with a house and he keeps saltwater fish as well) and started feeding them right away. I took the other 5 and put them in my temp holding system 3 were fed from day one, 2 were not fed for 10 days then offered food only once before I returned home. 6 survived, I brought 5 home (I left one in the 55 he is still alive and doing well, becoming agressive to the point they may get rid of him). the 2 that did not get fed both got skinny and died, all of the others are still alive. I know it has only been 5 or 6 weeks since collection, but all are fat and I have kept ones I collected in Mexico and fed from day 1 for over 2 years.

I am convinced that at least some of the "impossible" to keep could be kept if the collecters/wholesalers handled certain sp better. These are just 2 of the fish on the list, if we could figure out what it took, SOME of them could become succesfully kept long term.

Just my own experiences and thoughts
 
Peter, one question you mentioned 'Sandhopper' in your species left to advanced keepers but didn't list reasons or exactly what genus of fish? Are you referring to the Parapercis spp. ? They are sometimes sold as 'lizard Blennies' , 'Sand perch' or 'Rockhoppers'. I've kept one and they eat readily but are ridiculously good jumper and will bully tankmates almost from the start.

I had a was I think was Parapercis schauinslandi which seem pretty common in the trade and are quite hardy with the caveats of aggression and jumping mentioned.
 
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