Risky Stocking Options For Your Marine And Nano Tanks

[steelhealr]

We thought it might be helpful to post a list of some risky choices to add or put into your marine tank or nano tank. Nothing is written in stone, but, perhaps the choices made below should be made with caution.

Larger Marine Tank

Fish
Tangs
Can be aggressive and especially intolerant of other tangs.
Their tail scalpels can inflict serious injuries on those whome it takes a dislike too


Lionfish
Unsafe with smaller fish in the same tank. Venomous barbs on its dorsal fins can iinflict painful injuries to the unwary

Moray Eels
Poor eyesight and powerful bites means this fish needs respect when hands are in the tank. Other fish can be see as a snack also.

Triggerfish
Powerful bites and their aggressive behaviour other fish and inverts need to be wary of these fish. So do you if your hands are in the tank.

Groupers
Relatively easy fish but its predatory nature means other fish are seen as food. They also grow very large.

Large Wrasse
Not reef safe and are known to predate on snails and inverts. They also have a habit of re-arranging rockworks to their ownliking. If this is allowed to fall then your glass could be in danger

Batfish
An extremly large fish and very difficult to feed. Very poor captivity reports and those that do survive will outgrow all but hte largest tanks.

Moorish idols
A delicate fish that is very difficult to feed. Poor captivity reports

Puffers
These tend to grow very large and need big tanks to house them. They can also give a nasty bite with their powwerful jaws (not reef safe of course)

Cowfish and Boxfish
These fish grow large and can give out a potent toxin in the tank if tey are stressed. The result of this is a dead fish along with the rest of the tank.

Frogfish
Not safe with other fish. Thier poor eyesight can mean they mistake your hands for food if you dont treat them with respect. Their mouths are large enough to consume fish almost twice their length

Scorpionfish
Venomous, including stonefish and toadfish and are also predatory.

Invertebrates
Anenomes
Very poor captivity records. Needs very high lighting and excellant water conditions (Not for beginners)

Cowries
Whilst not harmful to the owner, these can be a problem if kept inb a reef as they are indiscriminant feeders, not only will they eat algaes but also corals as well.

Larger Crabs
Opportunistic feeders and are capable of catching fish

Lobsters
Can give a nasty pinch. Can catch prey and eat it. They can also grow quite large

Boxing Shrimps
Even though they are sold as reef safe, these shrimps can corner, kill and eat other shrimps, crabs and fish. They can be extremly aggressive.

Urchins
Some have poisonous spines that can catch an unwary hand in the tank.

Starfish
Not all are reef safe and will eat corals. Very delicate and sensative to water peramters. They need very very careful acclimatisation.

Nudibranchs
Some are poisonous. All of them have very unique food requirements. Without this food they will starve and die.

Sponges
Never accept a sponge that has been removed from the water. Air pockets can forim in them and they will rot from within and die.

Sea Apples
Dificult to feed as they require fine plannktonic foods. If they get stressed or die then they can release toxins in the tank.

Flame Scallops
Poor captivity records. Difficult to feed. A tendancy to swim around the back of the tank and dissapear forever. Can carry parasites like Peacrabs within them.

Sea Cucumbers
Whilst relatively easy to keep, if they die then they can release toxins that are harmful to the tank.

Corals

Pussey Corals
An aggressive coral with powerful stings.

Colt Corals
An aggressive coral with a powerful sting

Bubble Corals
Powerful stings that are carried in sweeper tenticles. These can harm other corals that it comes into contact with.

Hammerhead
Powerful stings that are carried in sweeper tenticles. These can harm other corals that it comes into contact with.

Galaxia
Powerful stings that are carried in sweeper tenticles. These can harm other corals that it comes into contact with.

Elephant Ear Mushrooms
Grows large and are capable of eating unwary fish.

Goniopora
Very poor captive reports. Little is known about this corals needs and requirements.

Dendronepthya
Very poor captivity reports. Almost impossible to kept fully fed as it needs near constant supply of plankton due to it not needing sunlight for energy.

Elegance Coral
Powerful sting that can harm other corals.

Fire corals
Powerul sting that can even leave a burning sensation on human skin.

Substrate
Silicate Sand
Very poor at carrying life within it. Offers no buffer to water chemistry

Locally Collected Sand
Can carry toxins that are released when in the tank.


Nano Tank

Fish

• Hawkfish: risk to inverts; may eat your shrimp or snails; can be aggressive
• Some dottybacks: aggressive nature among many.
• Fish that exceed 4-5 inches (tangs, eg): excessive bioload; stress of reduced space leading to illness.
• Green mandarins: require large amounts of copepods and/or special feeding techniques: low survival rate.

Invertebrates

• Nudibranchs: specific diet and short lived; can be destroyed by intakes and pumps and can nuke the tank; can be delicate animals; some are poisonous
• Sponges: difficult to keep; any exposure to air may cause death and breakdown in the tank.
• Sea Apples: can nuke your tank with toxins.
• Anemones: requires expert water condtions and lighting; long-lived animals and should not be entrapped in a nano tank; if 'unhappy' will move about the aquarium and sting anything it contacts; death may crash your tank.
• Flame Scallops: filter feeders and difficult to feed; moves about tank; will crash your tank if it dies which is most likely.
• Sea Cucumbers: may invert it's GI system and secrete toxins; tank crash.
• Sea Stars: inadequate volume to graze and survive; high probably of starvation; tank crash when it dies.
• Various crabs: Sally Lightfoots, Arrow crabs: SLF's pick at corals; Arrow crabs can trap and eat your fish.
• Coral Banded Shrimp (CBS): can trap your fish and eat them while they sleep.
• Purple reef lobster: may trap and eat fish; may nibble at corals.
• Certain featherdusters and coco worms: although listed as easy they are filter feeders; amount of plankton necessary for good health may overload the tank; large worms may nuke the tank when dead.

Corals

• Elegance: usually short-lived, currently under study by Eric Borneman for viral etiology; nasty stingers.
• Goniopora/Flowepot: nasy sting, difficult to keep.
• Galaxia: long sweepers and very powerful sting
• Dendronephthya: one of the most difficult corals in the world to keep alive in a home aquarium
• Non-photosynthetic gorgonians: amount of plankton needed to keep them alive may overload your nano reef. Generally very difficult to keep.
• Close combination and proximity of certain softies and LPS (eg, Devil's Hand and LPS): close proximity causes secretion of terpenoids and 'turf wars'
• Corals that can overrun the tank (yellow colony polyps, xenia, GSP, larger soft mushrooms)

Macroalgae

• Caulerpa: can go sexual and can take over the LR with 'rhizomes'
• Caution with any macroalgae placed in the main tank

Substrate

• Crushed coral shell: may trap detritus and be inhospitable to sandsifting animals.
• Silica sand (playsand): no buffering capability; may predispose to algae blooms

 

[fish_keeper2]

could you give an explanation to y these are risky options for tanks. i think it will help the newbs out a lot. im particularly interested why certian feather dusters and coco worms along with arrow crabs are risky.

 

[Navarre]

OK i have updated the large tank section so you can see why they are considered risky.
Im sure SH will update the Nano section in due course.

 

[SkiFletch]

Perhaps you should add Parrotfish since they're not reef safe (man they love to munch rocks and hard corals). Also maybe mention PB tangs especially with their innate ability to catch ich.

 

[fish_keeper2]

thanks guys for explaning y these are possible risks.

 

[Opcn]

I think perhaps you should amend in that eligance corals often die for no apperent reason, thanks.

 

[steelhealr]

It already says that....viral etiology and under study. SH

 

[Opcn]

I totally breazed over the one for Nanotanks

I was refering to the plain one

"Dendronepthya
Very poor captivity reports. Almost impossible to kept fully fed as it needs near constant supply of plankton due to it not needing sunlight for energy.

Elegance Coral
Powerful sting that can harm other corals.

Fire corals
Powerul sting that can even leave a burning sensation on human skin.
"

 

[andywg]

Can I be pedantic and request the lion fish entry is ammended to note the spines are venomous and not poisonous (as you don't need to eat them for there to be trouble).

Could also be useful mentioning that most of the Scorpaeniformes Family are venomous (including the toad/stone fish) and most are predatory.

Finally, you might want to ammend the frogfish to point out just how prolific their mouths are. They all tend to eat fish at least as long as themselves, and some are known to consume fish twice as long.

 

[steelhealr]

Done. SH

 

[atlantic reefer]

While I agree with most of this - I must disagree on the following -

Tangs
Can be aggressive and especially intolerant of other tangs.

While I agree that they can be agressive, they aren't always intolerant of other tangs. If given enough space (i.e. Tank Size) many tangs can coincide in a tank - take a look - www.oregonreef.com - sure thats a huge tank but even in a 75 gallon tank you can house 2 - 3 tangs depending on the species.

Anenomes
Very poor captivity records. Needs very high lighting and excellant water conditions (Not for beginners)

While they may have very poor captivity records, this is mainly with beginners and with certain species such as H. Magnifica. Most of the most commonly kept anemone - E. Quadricolor - do very well in reefers tanks along with the LTA. The hardest keep ones are the Carpet Anemones, Sebae Anemones and the previously mentioned H. Magnifica.

Colt Corals
An aggressive coral with a powerful sting

This I find as false unless we are talking about two differet corals. From my experience Colt Corals do not sting. They are actually fairly safe corals. What they do is they release toxins when stressed and when competeing for growing space. They are actually one of the easiest corals and most reccomended - also from my experience. It is reccomended that they are placed upstream from hard corals as so the toxins won't affect the hard corals with their toxins.

Silicate Sand
Very poor at carrying life within it. Offers no buffer to water chemistry

I agree with this this. Just to add to it, what happens is the silicate can produce nutrients which lead to help with the production of nuisance algaes.

Shane

 

[steelhealr]

I agree with this this. Just to add to it, what happens is the silicate can produce nutrients which lead to help with the production of nuisance algaes.

Silicates do not produce nutrients but can foster the growth of nuisance algae. Silicates are mineral salts. The other cautions will stand. Although in the right experienced hands and with expert water conditions and superior lighting, anemones may do well, I'm sure my fellow mods will agree with me that they are NOT for beginners. Only the consciencious and experienced aquarist should keep them IMO. SH

 

[Navarre]

I agree with SH. Anenomes are notbeginners fish. Not only forthe reasons given above (which are enough IMO) but many beginners buy them simply to house clowns which is simply wrong. Clowns will host in far easier things such as sarcophytons.
Also the poor survival rates means that they are being depleted at dangersously high levels in the wild and this shoudld be stopped)

 

[Lynden]

I'll be annoying and add my disagreements.

Triggerfish
Powerful bites and their aggressive behaviour other fish and inverts need to be wary of these fish. So do you if your hands are in the tank.

The above is what you could call a "blanket statement". While I certainly agree with the fact that they are powerful fish, there are several Triggerfish that can be kept not only with small fish, but with shrimps. These are the planktonivore and pelagic triggers, that include the genera Melichthys, Xanthichthys, and Odonus, and the genus Sufflamen shows promise in this regard as well.

Batfish
An extremly large fish and very difficult to feed. Very poor captivity reports and those that do survive will outgrow all but the largest tanks.

Only to Platax pinnatus does the above statement apply to. Most of the Batfish are easy to feed, and although most grow quite large, they swim slowly, and the smaller specimens can be accomodated very easily in tanks as small as 120 gallons. I have also seen a report in which a specimen lived in a 55 gallon tank for 13 years, and on Wetwebmedia.com can be found the recommendation for tanks of at least 55 gallons to house smaller Platax.

Puffers
These tend to grow very large and need big tanks to house them. They can also give a nasty bite with their powwerful jaws (not reef safe of course)

There are numerous reports of Canthigaster and Diodon living in reef tanks and disturbing nothing. I consider these two genera reef-safe, though the Diodon species grow very large.

-Lynden

 

[andywg]

There are numerous reports of Canthigaster and Diodon living in reef tanks and disturbing nothing. I consider these two genera reef-safe, though the Diodon species grow very large.
-Lynden

On a nit picking point, one could state that anything from the Family Diodontidae is not strictly a pufferfish, but a porcupinefish or filefish (puffers being Family Tetraodontidae).

As to reef safe, there are reports of frogfish living in tanks with things and not eating them. Doesn't mean it is wise to consider them safe with the other animals. If we take the fishbase entry for Diodon holocanthus:

Juveniles pelagic to about 6-9 cm. Solitary. Feeds on mollusks, sea urchins, hermit crabs, and crabs at night

The above information is from Leis, J.M., (2001).

Furthermore, the entry for Canthigaster janthinoptera states:

Feeds on sponges, polychaetes, filamentous algae and on smaller quantities of tunicates, crustaceans, echinoderms and corals.

I would consider anything that is listed on fishbase as eating corals and sponges a risk in a reef aquarium. that is not to say it will always end in tragedy, but that there is a risk it will.

Based on that, one should consider it a risk keeping the fish with ornamental shrimps and crabs.