Skip to content

The Vastness of Aquatic Enclosures!

  • by
Betta on substrate

Aquarium Hobby at a Glance

There are many different types of aquarium-like enclosures a person can have in their home.  They range in all sorts of sizes and levels of difficulty but they are all unique in their own way. From micro enclosures like jarrariums to enormous saltwater aquariums and ponds, there is a niche for everyone! We will broadly talk about many different enclosures for aquatic animals and the level of difficulty of maintaining these enclosures. We will also talk about basic designs and variety in setups.

Aquatic Jarrariums

One of the easiest and probably cheapest enclosures for aquatic critters is what is called a jarrarium. A jarrarium can be very simple but also very complex. There are two main types of jarrarium, open or closed. One requires the lid to remain open for oxygen to exchange with water, allowing you to feed the inhabitants, clean the glass, and change the water if it becomes overgrown with algae. The closed jarrarium is filled with inhabitants and sealed in hopes that it will become a self-sustaining system. If built correctly closed systems can be self-sustaining for a few years.


The most important and expensive item needed for these types of setups is good glass containers that can hold water. For the most barebone jarrarium, a glass container is needed but the only additional material needed is a scoop of water and substrate from your local pond or lake. These water bodies usually are fully loaded with tiny critters such as dragonfly nymphs and snails. This type of jarrarium is called an eco-sphere. Once the water is scooped out, it’ll be quite murky in appearance, but give the loose substrate time to settle at the bottom of the container and it should clear up. Most people do not add any critters into an eco-sphere but instead observe what type of wildlife comes out of the substrate. Eco-spheres help give an insight into many different critters that are in a person’s local water systems. Many of these eco-spheres are short-lived but a great educational piece for kids and adults.

Open Jarrarium

A regular jarrarium usually consists of a soil part, a substrate part, and then the decor that is placed on top. This type of jarrarium usually takes a bit more planning. The use of live plants and mosses is almost a necessity to help intake nutrients in the water, help prevent algal blooms, and provide oxygen for the animals within. Also, live plants are far more beautiful than their plastic counterparts (in my opinion). The livestock is pretty limited for jarrariums. It is usually limited to shrimp, snails, and possibly a betta fish if the jar is large enough. Shrimp come in many gorgeous colors, varieties, and sizes but on the other hand, be careful with snails because some can infest your newly built jarrarium. The jarrarium placement is very important. Changing room temperatures can harm the critters in their enclosure. Most aquatic animals prefer stable water parameters, such as stable temperatures, otherwise, they can be stressed which can lead to death. The amount of light is also a factor to think about. Too much direct sunlight will cause algal blooms and also raise water temperatures and too little will cause your plants to wither away and die. Consider using an artificial light source such as a CFL light above the jarrarium.

In my opinion, jarrariums are a very fun, easy, and cheap way to get into the world of aquarium keeping. The cost could be as little as just needing to purchase a glass container, but it can still become a very diverse and unique ecosystem. Some jarrariums look like works of art and are gorgeous pieces of decor in a person’s home or office.


Next along the lines is freshwater keeping. There are hundreds of different types of freshwater systems a person can put together and it can get a little overwhelming to think about. Different critters require different pH levels, water temperatures, and so on. Also, thinking about live plants will determine the species of fish you can keep. In my opinion, the most important factor to determine the type of fish that can be kept together is the size of the aquarium, and once the size is determined, you can get into deciding what species of fish will be comfortable in that size of an enclosure. I have been in this hobby for ages and worked in the industry. It is terrible seeing fish brought into the store that has damaged or misshapen bodies because they were forced to live in an aquarium that was too small for them.

From experience, a fish won’t stop growing because of the size of the aquarium. The fish’s growth will be stunted and it will cause its overall health to decline. Anyway, once the aquarium size is chosen the next step is to decide on the fish and decor. To start, many choose the simple route of plastic plants and rocky decor which is perfectly fine, but others will decide on getting more in-depth and setting up an aquarium with live plants and mosses. Putting live plants into an aquarium opens up a new can of worms and potentially increases in difficulty of keeping the aquarium running successfully.

For ease and simplicity, many fish keepers begin their freshwater journey with fake plants, decor, substrate, hang on the back filter, and a simple LED light. This is the standard aquarium and the easiest route that can be taken. Once interest in the hobby continues, things can branch into more unique niches. Instead of a hang-on-the-back filter, maybe use a canister filter or no filter at all! Instead of a regular old light, a person can try using more intense lights that will give the ability to sustain plant life in the aquarium. The unique alterations that can be made are limitless but we will not be getting into the elaborate details in this article.


Paludariums are a little different from a standard aquarium. A paludarium has both a land mass and a water body inside of a glass box. This opens up many doors for hobbyists because now animals such as semi-terrestrial crabs, frogs, or other critters can be added into an enclosure. This type of setup requires a little more knowledge and work to put together. There is quite a bit of planning that must be done before creating a paludarium.

Unfortunately, the limited size of the paludariums does not allow for species mixing. For example, mixing fiddler crabs with fire-belly toads. There is a great chance they may become territorial in such a small space, see one another as potential food, or just compete for food within the enclosure. This could lead to stressful situations for the animals and possibly put them in dangerous situations.

There are many things to consider when setting up a paludarium such as: What animal will you be keeping? Do you want water filtration? Do you want a waterfall setup? How deep do you want the water body? How much landmass? What plants do you want to keep? What kind of fish? The questions go on and on, but I am trying to get your mind thinking of some of the considerations that need to be taken for a paludarium.

Setting up and keeping a paludarium running is more difficult than setting up a freshwater aquarium. It takes far more planning to get the design right and deciding what terrestrial and aquatic animals to put it can be a challenge.


Many people use these terms interchangeably but there is a difference between the two. A terrarium is designed to primarily raise plants and a vivarium is used to house an animal. A terrarium can have animals but it can just be a glass enclosure filled with unique and exotic plants. On the other hand, a vivarium is designed to house and recreate an animal’s habitat. Common animals that are placed in vivariums are Dart frogs, geckos, and frogs. Vivariums and terrariums do not have a water body to house fish and other aquatic animals but a vivarium may have a water dish for the critters to drink from. They can be microhabitats or enormous enclosures that fill a whole room’s wall. Terrariums and vivariums are easier to set up and maintain than a paludarium but are a little harder to keep than a freshwater aquarium.


There is a lot of intimidation for aquarists that are thinking of transitioning into keeping saltwater aquariums. I would not set up a saltwater aquarium as a beginner hobbyist. I would gain knowledge about a freshwater aquariums, dip my toes in live plants, and research saltwater aquarium setups and keeping. Once all that experience and knowledge is gained, only then would I consider setting up a saltwater aquarium. Keeping a saltwater aquarium is not that hard. Keeping it well is where the challenge is and the cost of setup and maintaining it is what scares many away. Try freshwater and if you enjoy fish keeping consider setting up a saltwater aquarium.

The two primary niches of keeping saltwater aquariums are reef tanks or fish only. Many who set up reef aquariums are doing it to end up growing coral in their aquarium. There are many critters in the saltwater hobby that are not compatible with reef aquariums. For example, pufferfish wholeheartedly love devouring hermits and snails that would normally be found in a reef. Parrot fish will graze down your stony coral with ease. There are starfish and urchins that will also destroy a reef system. These are just a few examples of incompatibilities between animals. Decide what fish you would like in your aquarium and that will determine whether a reef tank is good for you.

Fish Only Aquarium Setup

Fish-only aquariums will not have corals and may or may not do well with crustaceans. Predatory aquariums are usually why hobbyists do not build a reef aquariums. Common critters that are put into fish only systems are angelfish, lionfish, eels, pufferfish, parrotfish, wrasses, stingrays, and many more. This type of setup will need a large filter because of the dietary needs of most of the animals. A sump system is recommended with a very good protein skimmer. Usually predatory aquariums and fish only setups are large (125+ gallons). This is because many of your predatory fish get very large.

Reef Aquarium Setup

Reef aquariums are quite different. They need good lights for corals, they will have crustaceans, and they can be very small or very big. I would still recommend a sump system with a protein skimmer for reefs but I would also look into setting up a refugium in your sump for additional filtration. Larger systems are easier to maintain but there is quite a fondness for nano reefs as well.

There are many different types of coral which broaden the spectrum even more. SPS corals need pristine water conditions so are usually kept in an SPS reef aquarium, while other corals like zoas and leathers do need specific parameters and can be put into a mixed reef or a species-specific aquarium of their own.

There are hundreds of different reef-compatible fish and crustaceans. I will not be going into the details of this because there are so many. Think of the type of fish you would like and research what size fish tank it requires and whether it is reef safe. Also, check the temperament of the fish. Many are very peaceful but others will get territorial. These are the main parameters for these fish.

Saltwater aquariums will easily cost an aquarists hundreds to thousands of dollars to set up. Reef systems are especially costly due to the lighting needs and the addition of quite a bit of live rock. That is why making sure this hobby is for you is important before walking down this path. Saltwater aquariums are for hobbyists who know a thing or two about aquariums and understand how water systems work.


Ponds are not as common in the hobby as the others. Many people do not have a yard large enough for a pond. Regardless, they are a great place to relax. The primary fish kept in a pond is a koi fish. They are very similar to goldfish but are usually longer and grow larger. Their colors are magnificent! Other animals that may naturally come around ponds are frogs and turtles.

Ponds also can have different plant matter growing in them. Lillies and floating water lettuce are two that come to mind that is quite commonly found in home ponds. They are a nice addition and provide cover for your fish from predators such as raccoons and herons. Also adding a little bit of green color never hurt.

There are many things to consider when setting up a pond. They can get quite expensive. Picking a location is important. More sunlight will lead to more algae growth in your pond but also too much shade may cause other plants from flourishing inside. During the initial setup, choosing a pond liner is very important. A durable liner may cost more at first but will hopefully prevent leaks from happening which will save you money and stress in the long run. A waterfall feature will add great aeration to the pond but a pond pump costs a lot of money! Think about other aerating fixtures to get oxygen into your system.

The following is more dependent on where you live. In the United States, the Midwest goes through four seasons. Pumps need to be shut off for the winter, koi need to be either taken inside or fattened up for the winter, springtime will lead to pond cleaning, and so on. The pond needs to be deep enough for fish to be kept in there through winter. These are obstacles that need to be overcome in the Midwest but it’s not as big of a problem in warm states like Florida or Arizona.

Ponds are wonderful! They are a great place just to cool down and enjoy nature in your backyard but they are quite difficult to maintain and can be costly. The chance of losing a fish to predators is unfortunate but it’s a risk that is taken by pond keepers due to its beauty! Quite a bit of research and preparation should be conducted before setting up a pond!