Basic Steps on How to Make a Terrarium (using Fish Tank)

Basic Steps on How to Make a Terrarium (using Fish Tank)

Aside from aquascaping, gardening is also one the most arguably popular and satisfying DIY pursuits amidst pandemic. However, the rewarding feeling from every beautiful bloom and bountiful harvest are products of diligent maintenance. That is why some might get discouraged for not all of us have time and space for such laborious activity. 

Even so, you can still enjoy gardening in a simple and fuss-free way thanks to terrariums.

What is a Terrarium?

Terrarium, also called a glass garden, is a type of a vivarium just like aquarium. 

This enclosure is mostly made of transparent glass containers and has a collection of small, decorative plants that sometimes includes small animals. 

It can serve different purposes such as decoration, scientific observation, and as well as plants or animal propagation. 

How to DIY Setup a Fish Tank Terrarium

A great part of DIY is that you can create unique output based on your creative imagination. As aquasapers we sure have lots of aquariums to spare, why not use one to try something new. You can use your old fish tank to supplement your lack of garden space. You see, a terrarium is like an aquarium, the only difference is, you put plants instead of fish.

Basic Tool

  • Spoon
  • Tweezers(optional)



  1. Fish tank
  2. Plants that you want to put in your terrarium. It is best to choose foliage plants and plants that grow slowly. For example:
  • Ferns 
  • Carnivorous plants 
  • Airplants 
  • Succulents
  • Peperomia
  • Moss(optional)
  1. Pea gravel or Polished rocks
  2. Activated Charcoal pebbles 
  3. Sterile potting soil 
  4. Small species of animals(optional)
  5. Fun décor(optional)


Step 1

Make sure to clean the aquarium before using it. You can use an all-purpose household cleaner and a scrub pad to get the worst fishy smell out . After this, rinse the tank with hot water. Then, dry it with cloth in order to make sure that you remove all the cleaning agent residue.  

Step 2

Pour in enough gravel to fill the bottom 2–r centimetres of the aquarium(about 1-2 inch thick). The gravel will serve as a drainage system for your fish tank terrarium so that the roots of your plants will not rot.

Step 3

Add a 1/2-inch layer of activated charcoal pebbles and mix it with the gravel. Activated charcoal will filter the air inside your fish tank terrarium.

Step 4

Add a layer of sphagnum moss with 1-2 inches thick to cover the gravel and the charcoal. It is not necessary but the moss will help prevent the soil from sinking into the mixed gravel and charcoal. 

Step 5

Pre-moisten the potting soil before adding to the bottom of your fish tank. The amount of soil you add will depend on the size of your fish tank as well as the type and size of plants that you want to grow. The soil can be distributed evenly or you can use your aquascaping expertise when distributing the soil. 

Step 6

It's time to add the plant that you choose for your fish tank terrarium. If you discover that your plants' size or root mass is too big for your fish tank, simply divide the plant at its roots to fit its size and scale to your fish tank. 

You can create planting holes in the soil and place each plant where you want to designate each. After planting, firm the soil around the base of each plant and then mist after planting to settle the soil. 

For animals. Insects, spiders, scorpions, amphibians, lizards, snakes and turtles are the animal groups most commonly kept in terrariums.

Step 7

Remove any dirt particles from the foliage of your plants as well as the inside glass of your fish tank. 

To finish off, you can add decorative objects such as twigs, miniature figurines, just any pieces you desire. Some even find it appealing to use ghostwood and manzanita driftwoods due to their rot resistance and branchy look. 

How will you care for your Fish Tank Terrarium?

The idea of terrarium is to mimic an ecosphere. This means that the environment inside the enclosure will take care of itself. Additionally, the plants that are suitable for a terrarium require very small amounts of nutrients and require very little care to maintain. So caring for your fish tank terrarium can easily be done. 

You can check your fish tank terrarium once in a while to monitor your plants hydration. If you notice that too much humidity builds up in your enclosure, try venting it. Remember, fish tanks' are made of transparent glass that can magnify sun rays. Direct sunlight can harm your plants for it can raise the temperature level inside your fish tank terrarium. Remove any yellowing or dead leaves, as they can mildew easily. Do not fertilize your plant, it could make your plant grow too big for your fish tank. Occasionally trim your plants to keep it small. 


As you could see, a lack of space is not hindrance for a hobby. Especially if we used our creative and resourceful minds. As aquascapers we love to see the fruit of our hard work and passion. And as much as you love Aquascaping, I'm sure you will also love Terrarium scaping!

Leave a comment

Please note, comments must be approved before they are published