Ten fish that the trade might be better without!


Ten fish that the trade might be better without!

I think that any of us could conjure up at a moment's notice a list of dozens of fish that we feel the industry would be better not having in it. But I want to highlight a few that still seem to be doing the rounds, and the problems with them.


The easiest targets would obviously be those that get too damned large for the average hobbyist’s tank, and I’ve listed a couple of my choice whoppers.

But at the same count there are those fish that are awkward feeders, disease riddled death traps, and serial killing psychopaths. I offer a choice of my ten worst fish to stumble upon, and my reasons for giving these fish a very wide berth.

Elephant nose mormyrids (pictured above)

Why not take about £15 in cash and burn it? Actually, take another fiver and torch that too, to account for the food you’ll offer until the poor beast starves to death.

Elephant noses are the big thing in curiosity fish, and I adore them as much as the next man or woman. But they’re not a sensible choice, unless you’re in a position to stay home all day, feeding continuously.

These nervous fish aren’t even easy to monitor. Get them home and the first thing they’ll do is go into hiding, finding a cave or tunnel somewhere.

They’ll emerge at feeding time, usually through starving desperation, and then they’ll probe around and reject all but the choicest of live or frozen foods.

Even the professionals try to avoid keeping these. There’s nothing more disheartening than pouring in endless supplies of bloodworm and watching the fish getting thinner and thinner, day after day, until it eventually rolls over.

Most people don’t even get the substrate right for these fish. They require soft, almost muddy substrates into which they can shove their handsome proboscis, and they squabble amongst themselves when kept in multiples.

Take note, and don’t learn how difficult a fish this is the hard way…

Pangasius catfish

Why? Just why?

This is the mother of all pitfalls for the new and eager hobbyist. I mean, this is a fish now farmed commercially for food, and we’re keeping these in home aquaria.

They’re popular as food for two reasons. Firstly, they grow big. Secondly, they grow big fast. Two reasons why we as home aquarists would want to avoid a fish, surely?

Bred on such a commercial scale as they are, these are cheap additions to anyone’s tank. The young ones have appeal with their sharky appearance, and for catfish they’re always out and about, where the hobbyist can see them.

They start off well, with their omnivorous tendencies, and they fatten out quickly, becoming plump and amiable centre pieces. And then that diet starts to drift into the meatier side of tank friendly, with small fish vanishing as adult shark cats start to develop teeth – and an understanding of how to use them.

Oh, and did I mention that they get over a metre long? Because they do.

Common goldfish (aquarium)

Feel free to shout at me over this, but I’m sticking to my guns. The humble goldfish easily represents the most abused pet in the UK.

They may not get huge like a Shark cat, and they’re easy enough to feed, but they never reach their potential lifespans in captivity.

"But they’re what get people into fishkeeping!" I’ll hear people saying. Utter tosh, we all know there are better alternatives for a starter with an unheated tank, and I wonder just how many of these things are consigned away to a cramped, shortened life because of laziness in selling. Take a few minutes out to explain the size, the eventual tank needed, the longevity of the fish and you’ll start to see people taking a shine to those danios or minnows after all.

Oh, and I’m not letting manufacturers off the hook with this one either. You want to sell small tanks? Take those pictures of goldfish off of the front of the boxes. I guarantee you right here and now that the overwhelming majority of hobbyists and retailers will give you kudos for it.

Moorish idol

Need I say more? Popularised by the film 'Finding Nemo,' these had pretty much disappeared off of the radar until then. Now they’re back in the loop, slowly starving to death in dealers’ and hobbyist’s tanks.

They’ll wreak a little havoc on the way out, too, picking at polyps and corals in their desperation for something to consume. In the wild they feed on sponges and tunicates as their menu of choice, and these are neither easy nor cheap things to come across with any sort of reliability.

They are incredibly pretty fish, up there in my top five 'lookers.' But that’s how I like them, looking healthy and active, which is why I feel a little bit of contempt whenever I see one of these on my rounds.

Wild Moorish idols are lovely. Captive ones are usually just waiting to die.


I’d have thought this one would be a no-brainer, but that just shows what I know.

Let’s take a pelagic, ocean faring fish that latches itself to sharks, like the Lemon shark above (picture by Albert Kok, Creative Commons) and travels colossal distances, and often feeds on the faeces of whichever host it’s adhered to, and let’s stick said fish into a 6' x2 'x 2' tank and wonder why it goes downhill fast.

I’ve never understood what it is that Remora keepers are trying to prove, but I’m pretty sure that they’re not flagging themselves as the most ethical of hobbyists around.

Farmed guppies

So, let's get one thing straight here. I’m not having a pop at all farmed guppies, and I’m not even going to point my finger in the direction of the hemisphere in which these guppies originate, but there is a sizeable chunk of these fish that shouldn’t be getting out of their countries of export, let alone accepted into the UK.

The guppy has been a human triumph of disease engineering. We took a fish that used to be pretty hardy, and made it into the most disease-riddled mongrel going. Smothered in tetrahymena, drizzled with a generous dash of columnaris and bagged for export, I’m amazed that many retailers still bother to syphon their money away with these fish.

And it seems to be the case that the fancier the fish, the more likely it is to be carrying everything under the sun.

So, if you’re thinking of buying some guppies from a tank where there are dead fish on the bottom, and the remaining few are hanging in the water with eroded fins and a blank 'please kill me' look in their eyes, then maybe you’d be better off picking up a hand grenade and hurling that into your home aquarium instead. You’ll get roughly the same result.

Mbu puffer

These have come up a few times now, and I have to concede that after some critical thinking, the trade really might be better off without these.

Given that they tend to sit in dealer’s tanks for months at a time, growing fat on shellfish, I often wonder if the space would be better given to something that might actually sell.

When they are bought, the owner then has the delight of sitting back and watching the things slowly grow to 90cm/36" or so. If really lucky, he or she might also need to arrange to take it to a vet to trim an overgrown beak – a procedure that doesn’t always go well with blindness and other horrific symptoms reported by owners that have had their fish anaesthetised.

One thing that always strikes me about Mbus is that I very, very rarely see them in public aquaria, the usual final destination for big fish. My immediate thought is that if they’re not getting to the public aquarium stage, then what’s happening to them in between? Where are all these Mbus going?

Featherfin Synodontis

I hate to turn on the Synodontids, as I love them so very dearly. But this species in particular should come with a health warning for the sake of other tankmates.

Young Featherfins are so cute that they make me start talking in baby-speak. They are, quite simply, adorable. (Awww, dey so adooorwable!) And then they grow up and kill everything.

I’ve no idea when these catfish gain a taste for flesh, but somewhere along their development they realise that tetras and barbs are a food source. Soon after this they realise that scales and mucous can be stripped from the bodies of gourami and angelfish. Then they work out that eyes can be sucked out of heads. Finally, they discover how soft and tender fins are, and proceed to rag all and sundry about. Oddly, they still manage to look quite cute throughout all of this, and it’s only when the fishkeeper realises that the Synodontis is the only fish in his or her community tank that isn’t obliterated that the penny finally drops.

As serial killers go, they’re very attractive. But apparently, so was Ted Bundy, and I’d rather not have been stuck in a room with him for too long.


I might as well have a stab at the pond world now that I’m on an angry roll.

The sterlet is, quite simply, one of the most nonsensical fish a person could opt for in a home pond. Let’s be honest, most domestic ponds aren’t really that large, maybe a couple of thousand gallons for a ‘bigun.’

And these ponds generally get blanketweed in them. Never has a fish come so unstuck in the presence of algae as the sterlet. They snag their knobbly, sharp bodies in the spider’s web of green filaments, gradually mummify themselves and then die of exhaustion trying to break free. Nasty.

They’re as dumb as a box of rocks, too. Lumbering around the pond, all a heron has to do is go to sleep with its beak in the water and eventually the sterlet will wander over and swim down its throat, saving the bird a whole lot of bother.

But they also struggle with heat. Small ponds during a British summer will happily hit the mid-twenties, and for these animals with their high oxygen demands just cannot cope in such sweltering temperatures.

No, this is a fish suited to cooler climates than our own, and in considerably bigger bodies of water.

Common plec

Yeah, I’ve opened a can of worms here, and pedants will be quick to pull me up over which species I mean by ‘common’ plec. My answer to you is that it’s the big brown oxen of a thing that seems to dominate any community tank over five years old. Feel free to lump the Sailfin plec in with this one, too. Same problem applies.

Ancistrus are off of the hook. I love you Ancistrus, go forth and inhabit medium sized communities the globe over. You have my blessing.

But the big brute that simply goes by the ominous name of ‘plec’ has served its time in the field. It’s been housed alongside Oscars, it’s been crammed into tanks where it’s been pestered by African cichlids, and it’s sat glumly at the bottom of many a three foot community wondering whether there really is more to life.

There’s no need anymore. We have a wealth of small loricariids at our disposal, some pretty, some secretive, some outright ugly, but all better suited to a smaller aquarium than this long abused fish.

I can assure you that the first impression that a public aquarist gets when one of these adult, stunted fish is lumbered upon them is not one of sheer delight. They’ll be thinking pretty much the same as me: "Why the hell did you buy a fish you couldn’t look after?"

So there you have my personal ten. I’d be keen to hear the choice ten of others, and that’s what the comment box below is for. So go for it. Have a rant, get it off your chest.

You’ll feel so much better for it, just like I do now.

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