What is a Jarrarium?

A jarrarium is a micro-aquarium made from a combination of household materials and local natural resources that allows you to observe aquatic life. The jarrarium is a window into those unknowable depths that can be placed in a location more conducive to staying dry and avoiding mosquitoes. The best part? You can make one in a couple of hours for no money at all.

Why not just have an aquarium?

Having an aquarium is a very rewarding, but very expensive hobby. Once you decide to upgrade from a betta in a cup you have to consider all manner of expenses: varied foods, large tanks, lights, filters, heaters, and animal costs to name a few. Some fish at the pet store cost more than $100! That’s where jarrariums come in. By making a self-sustaining ecosystem, we cut out a lot of those maintenance costs which make up the bulk of aquarium expenses. Additionally, we intentionally limit our selection of animals – both to reduce maintenance and to be humane.


This cost $400,000! (Photo: javedfisheries.com)

Part of the reason that aquaria tend to be cost-prohibitive is that many popular species of fish require specific environmental parameters to remain healthy. Even regular goldfish are supposed to have a tank that’s at least 30 gallons! Proper care of a betta fish is not in a tiny, ornamental tank or vase – it should be in a container of no less than 15 gallons. Just as you wouldn’t raise a tiger in your bathroom (even though it technically fits), you shouldn’t raise a cichlid fish in a punch bowl. Not only is it unfair to the animal, it also keeps them in a state of permanent stress which will inevitably lead to illness.

Why should I make a Jarrarium, then?

Just because you can’t have fish, doesn’t mean jarrariums are boring! There are lots of perfectly interesting animals (and plants!) that will thrive in such an environment. There are many varieties of snails and shrimp that adapt well to jarrariums. Between those animals and a diverse array of substrate-dwelling invertebrates, your jar will always have something going on.



If you aren’t sure what an invertebrate is – don’t worry! As an educational tool, jarrariums are unparalleled. They are the perfect introduction to all manner of disciplines: biology, ecology, chemistry, and botany to name a few. The system is both simple enough that you can avoid all that science stuff if you want, but complex enough for inquisitive minds to get their feet wet in aquatic ecology. You can use jarrariums as an experiment to guide children’s interest in the sciences, or at least to get them to be quiet for a while. They will jump at the opportunity to play god with their own little world, and hopefully be inspired to pursue knowledge as they watch their jarrarium change over time.

If you like a challenge, you can take it one step further and create a sealed jarrarium, attempting to find the elusive balance of nutrients and organisms that will allow your ecosystem to survive in perpetuity.

Continue in the series to learn how to make your very own jarrarium! The next post discusses the question: Are Jarrariums really self-sustaining?