But within a few days, it was normality. Get into work at 8:45, put the kettle on, search for dying fish while chatting to your colleagues, smash the fish against the wall and throw the corpses in the Dead Fish Bag, throw the Dead Fish Bag in the bin, make a cup of tea, then open the shop for customers.

For larger fish, such as carp, we need to resort to different means. For a start, the force required to kill a big carp would probably break the net you use to kill it, and nets are expensive. For most fish over about 10-15 centimeters, the preferred method is to put them in a sturdy plastic bag and then hit them on the head with a half-brick. Hit them too lightly, and they won't be quite dead -- not good. Hit too hard, and the bags break, and you literally end up with blood on your hands.

With armored fish, like sterlets, that's still not enough force, so we stomp on them. It feels similar to stepping on a snail. There's the crunch, followed by the gooey center. And no matter how many times you do it, you always make the mistake of looking in the bag afterwards. You can barely see the pulped remains of the fish for all the blood.

Sometimes, you have to kill lots at once, chemically, leaving you with 100 fish in a 20-pound bag. The odd thing is that it doesn't feel as bad as killing a single fish -- at least, not to me personally. Likewise, the guy I do these culls with is too squeamish to kill individuals, but he's fine with mass kills. When it's not a violent and bloody method of euthanasia, it feels all right; like we're not actually killing them. It's like that old saying goes -- "Kill one fish and you're a murderer. Kill a million and you're a conqueror." Well, that or a cook at Long John Silver's. But you can tell people you're a conqueror if you want.

These are all variants of goldfish -- the bubble eye, the ranchu, and the telescope -- and they're the end results of Man playing God without an instruction manual, missing like half of the pieces, and with the wrong game board. None would last five minutes in the wild. In the case of the bubble fish, those sacs are easily quadruple the size of its head and make it very difficult to swim. And their eyes pop when they rub against something sharp. Pop like a balloon. Naturally, this leaves the fish blind in that eye, with a gaping hole on the side of its head.

Then there's the blood parrot:

Fanghong/Wiki Commons

You know these rascals must be happy, because they're smiling at you! But that adorable artificially-bred mouth keeps its jaws from moving, so it's forced to try to chew with its throat muscles. If it shares a tank with other fish, the others will always bully it and take its food.

And buyers love the expensive two-headed arowana, because at a certain point, we stop pretending and admit that we're spawning monsters:

Arowana.co.uk

It (they?) can't swim properly, and often gets sucked into the tank pump. For which it is probably thankful.

No, the fish that go out of their way to bite you are cichlids, and they're real bastards. Once they've decided that an area is theirs, they will guard it. They have teeth, and woe betide anyone who goes anywhere near a breeding pair of them. During the first few weeks I worked in an aquarium, a customer brought in a breeding pair of Midas Cichlids that they couldn't look after any more. The other staff told me I needed to clean the glass of their tank. The next thing I knew, both extremely angry fish were mauling my hand. Now, this was my first job (I was 15), and I did not want to lose it, so I did what I was told and continued to clean the tank. I eventually realized why everyone was laughing, and never trusted again. By the end of it, my hand was nicely decked out in blood and cuts.

George Baily

When they're startled, fish will sometimes jump out of the water. I'm sure this is a good idea in nature, as bodies of water in the wild tend not to have sheer sides. Aquariums do. Part of the job is finding the desiccated corpses of fish that decided to make a bid for freedom weeks, if not months, ago. I kept my pet jaguar cichlid in a large open-top tank from which he could see the entire shop. One time, I was leaning over his tank, and he jumped out and bit me square on the nose. Oddly, customers tend not to believe it when you're holding a bloody tissue and you tell them it's because a fish bit you.

Other fish are venomous, like lionfish and foxfaces. If you ever go diving, everyone will warn you to stay the f**k away from lionfish, but we stock them anyway. If you're allergic to bee stings, you're probably also allergic to lionfish, and an untreated sting will kill you. One of my co-workers was indeed allergic to bee stings, so my boss, ever the jokester, assigned him to clean the lionfish tanks every day. I guess he'd grown jaded by all the fish killings and wanted to try his hand at offing a human.

They don't leave a corpse when they die. They liquefy, forming a thick, white ooze with flecks of red running through it, like someone dumped a ladle full of bloodied semen in the tank. The stench is worse than the sight. Worse still is the process of removing it.

Because they're a liquid, you can't scoop it out with a net. Instead, you have to siphon it out with a length of hose. In order to start the siphoning, you need to put one end of the hose in the tank and suck on the other end. When one coworker tried this, he ended up with a mouthful of rank jizz monster corpse goo. And then he accidentally swallowed. He threw up, naturally. Thinking about it, perhaps you will as well.

Another part of the job involves siphoning the crap out of the gravel in the bottom of the tank. This works in the same way, and sometimes has the same consequences: a mouthful of a liquid you'd rather not experience (in this case, fish effluence). Surprisingly, it doesn't taste that bad -- kind of earthy. Don't get me wrong; you don't want to drink it. But after a while, a mouth full of fish s**t becomes another part of the job.

Fisheries and Oceans Canada

The drains are another issue. Aquarium drains vary from "merely unpleasant" to "the devil's burrito farts." All the fish waste you're siphoning out of the tanks ends up going down the drains, along with the occasional dead fish, and there they rot and rot and rot. The pipes swell with the crap of the dead.

Goldfish are supposed to grow to more than a foot long, which means they should live somewhere much larger than a foot, like a 40-gallon tank. Unscrupulous pet stores tell buyers that the fish will never grow larger than their bowl or tank can accommodate, and that's technically true, because they'll die first.

Go into any pet store and you'll see a load of small cheap plastic aquariums for sale, usually with colorful pictures of cartoon fish on the box. They're advertised as goldfish tanks for kids, and they sell like hotcakes. And they're absolute wank. If you're lucky, they'll come with a small, inefficient filter which may keep the water clean for a few tiny fish, like guppies or minnows, but which is in no way suitable for goldfish. Think of goldfish as disposable pets that soon die, get flushed, and are then replaced? In the wild, they have an average lifespan of more than 10 years.

Marina/Amazon.com

You're also killing your fish by feeding it. Fish food instructions say to feed the fish two to three times a day (the more you feed them, the more you have to buy). But doing so often leads to death by overfeeding. Aquariums only feed fish once a day or less. Fish always look hungry, but that means they're healthy, not that you have to feed them more.

Aquariums will usually offer a refund if your fish dies, provided that you give us a water sample we can test. Almost always, the customer's water sample is basically liquid ammonia, because it was thick with waste due to overfeeding.

Michael Zwahlen/EyeEm/Getty Images

But sometimes, fish disasters go a little beyond benevolent ignorance. Let me introduce you to a little something called ...

A battle tank is (as the name suggests) a tank full of fish that fight amongst each other for the pet owner's amusement. We don't sell them as pre-made options or talk to buyers about the subject, so it's up to an individual sadist to buy a tank and then stock it with whatever combo leads to the craziest results. Popular choices in these tanks are large cichlids and catfish -- big, territorial fish with big mouths. The idea is that the fish in the tank are evenly matched in their capacity for destruction.

wildestanimal/Moment/Getty

Now, fish fight. That goes without saying. They're animals, and that's what animals do. And in any tank containing these larger territorial fish, there will be the odd dispute. But provided there's enough space in the tank, it'll be over soon. The weaker fish will almost always back down.

A normal cichlid fight goes something like this:

-- Cichlids square off
-- Cichlids flare their gills up and generally try to look big
-- Cichlids push each other around with their mouths for a while
-- Cichlid that is weakest swims off and sulks

If you like, keep the audio off and pretend they're f*****g.

This is not what happens in a battle tank. In a battle tank, it's purposely so crowded that there's nowhere for the weaker fish to escape to. With this kind of tank, you inevitably end up with battered, cut-up fish. Cuts lead to infections. Infections lead to deaths. The people who set up these tanks don't necessarily want the fish to kill one another. They just want the tank to be chaotic as possible. But you don't throw people in the Thunderdome expecting it to end in snuggles.

Sure, I've killed a lot of fish in my time, for a number of reasons -- to put them out of their suffering, to save the company time and money, or simply because I was told to. But I'm glad that I drew the line at "because I like to watch them die."

Ryan Menezes is an editor and interviewer here at Cracked. Follow him on Twitter for stuff cut from articles and other things no one should see.

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