Aquariums and zoos are essentials for young families looking for something to do on a rainy day or field trip. Seeing a bunch of animals and marine life that aren't pets is incredibly invigorating for people of all ages.

The older we get, though, the more we begin to wonder what life is like for both those working at the aquariums and the animals inside those tanks. Are these animals really being taken care of with utmost care and respect? Likewise, how much training do aquarium workers actually need in order to land a job at one of the hundreds of aquariums worldwide?

Before you head over to the closest aquarium to be face-to-face with a shark and thousands of fish, here are 10 interesting things we didn't know.

10 GETTING A JOB IS INCREDIBLY DIFFICULT

There are countless children who are looking to work with animals when they're older because they just love them so much. Whether it's working at a vet, a zoo, a pet store, or an aquarium — getting a job is very competitive.

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Not only will you need a serious degree in marine biology (and other correlating degrees) to work with marine life, it's also recommended to be scuba-certified and to have experience with marine life; whether that was through internships or other positions.

9 SEALS AND SHARKS EAT BETTER THAN US

Considering it's an aquarium's job to keep their marine life healthy and happy, their diets have a lot to do with that. According to Mental Floss, the fish given to animals like seals and sharks are checked thoroughly for bacteria and other diseases. In fact, most of these workers' time spent is in the kitchen preparing for food that's good enough for their sea-life friends. Even a writer from BuzzFeed headed over to an aquarium where he found sharks ate restaurant-quality fish that sometimes had added vitamins to ensure the shark's health.

8 MARINE LIFE CAN BE TRANSFERRED AND SEPARATED

Many aquariums work together in terms of finding mates and creating better habitats for animals that are growing in size or are just getting older. Trading animals can help with conservation and giving the animal a better environment to thrive in.

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Transfering and trading animals comes at a cost, though. Thanks to recent documentaries on life inside aquariums, we see larger mammals, like orcas and dolphins, are torn apart from their families. Babies are also taken away from their mothers before they have a chance to bond, which is traumatizing for both parent and child. This is just one of the fires aquariums are working on blowing out.

7 THERE'S AN AUTOPSY AFTER EVERY SINGLE DEATH

Knowing that most aquariums have a good heart and are trying to rescue and save animals who couldn't hack it in the wild, it's painful when an animal dies. To ensure the aquarium is treating the animals to the best of their ability, an autopsy is performed after every death, according to Mental Floss. If a fish was killed by another hostile fish, that's one thing; but other reasons could be due to bacteria and disease, which could affect other fish if the workers aren't careful.

6 OCTOPUSES ARE SNEAKY

If you've seen Finding Dory then you would understand that octopuses can be quite sneaky. In the film, Hank is trying his best to leave the glass jail he's in and get to another exhibit where he can be in peace.

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According to Business Insider, Hank wasn't just mimicking other animals in the movie — different breeds of octopuses do this in real life, too. In one instance, there was an octopus in Germany who squirted water on the lamp above its tank to kill the light. There was also a time when an octopus actually created a small flood in California by messing with the valves!

5 MARINE LIFE AREN'T JUST RESCUED, THEY'RE BRED IN CAPTIVITY AS WELL

When most of us think about the fish and wild marine life in aquariums, we tend to assume they were rescued from the wild. Aquariums and zoos are getting a lot of flack these days, so the way they treat and raise their marine life is under a microscope.

However, not all animals are rescued. Many aquariums breed their marine life as well. For those aquarium workers who collect eggs to make sure they're thriving, watching them mature and grow can be a special moment for workers.

4 TRAINING MARINE LIFE IS INCREDIBLY TIME-CONSUMING

We've seen the Sea World commercials of Killer Whales, dolphins, and seals doing all different kinds of tricks. From swimming with their trainer on their nose to playing basketball in the pool — these animals are way smarter than any of us realize.

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Most aquariums train their animals through positive reinforcement. Every time the mammal does something correctly, they get a treat. If treats don't work, sometimes a trainer will use a whistle of some kind to let the mammals know they're on the right track. Sometimes on trick can take as much as 30+ hours!

3 SHARKS ARE FED OFTEN (AND A LOT)

Have you ever gone to an aquarium and wondered why the sharks weren't devouring all of the fish swimming around them? Well, for starters, life isn't like the movie Jaws. Sharks don't kill things just because something is swimming by them. At the aquarium, life for sharks aren't much different, however, the staff makes sure to feed the sharks well and often to avoid eating any of the beautiful fish swimming around the shared habitat. If a shark isn't hungry, it's not going to go in for the kill.

2 WORKERS NEED TO BE FAMILIAR WITH PLUMBING, CLEANING, AND GETTING DOWN AND DIRTY

When you're days are spent caring for marine life, you have to be okay with getting down and dirty. You're most likely going to smell like fish, you'll have to get in the water sometimes, and you're going to become familiar with plumbing and cleaning,

There are constant issues with fish filters and pumps, causing non-plumbers in the aquarium to work on the fly whenever a problem arises.

1 THE CHEMICALS USED IN AQUARIUMS HAVE A BAD REPUTATION

So, how exactly do aquarium staff keep their tanks so clean and pure when the fish and mammals living inside can't be removed? Chemicals. Peta mentioned in some cases where "chlorine and copper sulfate" were used, larger mammals lost their sight and even had skin irritations, due to it being un-natural. In the wild, these mammals and fish don't need to worry about such things (unless it comes from pollution. Now that's a whole other conversation in itself). Likewise, due to the stress of being in a captive environment, many marine animals become mentally unwell and stir-crazy.

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