Aquatic Terrariums (Paludariums)

An aquatic terrarium, commonly referred to as a paludarium, is a type of terrarium that combines both terrestrial (land) and aquatic (water) elements. It is designed to simulate a natural environment where land and water meet, such as riverbanks, swamps, or mangroves.

Key Characteristics

Integrates both aquatic and terrestrial environments within a single enclosure. Includes a water section that can range from a small pond to a deeper aquarium-like area. Contains a terrestrial area with plants, soil, and sometimes small land-dwelling animals.Features a gradient or transition zone where the land meets the water, often planted with semi-aquatic plants.

Components of a Paludarium

Aquatic Area

Clean, fresh water is essential. This area can house fish, aquatic plants, and other water-dwelling organisms. A water filter is necessary to keep the aquatic environment clean and healthy. If housing tropical species, a heater might be needed to maintain the appropriate water temperature.

Terrestrial Area

Use a suitable substrate like coconut coir, sphagnum moss, or soil mix for the land section.

Select terrestrial and semi-aquatic plants that thrive in humid environments. Incorporate rocks, wood, and other decorations to mimic a natural landscape.

Transition Zone

Substrate Gradient: Gradually transition the substrate from the land to the water area.

Plant Selection: Use plants that can tolerate varying levels of moisture, such as mosses, ferns, and grasses.

Setting Up a Paludarium


Plan the layout, considering the needs of both land and aquatic inhabitants. Ensure you have all necessary equipment, including a suitable tank, filtration system, lighting, and heating.

Creating the Water Section:

Install Filtration: Set up the filter to maintain clean water. Fill the water section and dechlorinate if necessary. Add aquatic plants like Java moss, Anubias, or aquatic ferns.

Creating the Land Section:

Use substrate and hardscape materials to form the terrestrial area. Add plants suitable for high humidity, such as pothos, ferns, and mosses.

Establishing the Transition Zone:

Gradually slope the substrate from the land to the water.

Plant Semi-Aquatic Plants: Include plants that can thrive in both moist and submerged conditions, such as Cryptocoryne and marsh plants.

Final Touches:

Use full-spectrum lighting to support both aquatic and terrestrial plants. Introduce compatible animals, ensuring the species chosen can coexist harmoniously.

Differences from Other Terrariums

Unlike standard terrariums, paludariums include a significant water feature, often with live fish or other aquatic life.

Paludariums can support a wider range of biodiversity, including aquatic plants, fish, amphibians, and terrestrial plants and animals. The combination of land and water environments requires more complex maintenance, including water quality management and humidity control. Paludariums are generally more complex to design and maintain compared to traditional terrariums or aquariums due to the need to balance both land and water ecosystems.

Benefits of Paludariums

Provides a beautiful, dynamic display that mimics natural habitats. Supports a variety of plants and animals, creating a rich, interactive environment. An excellent opportunity to learn about different ecosystems and their interactions.


A paludarium is a fascinating type of terrarium that blends aquatic and terrestrial environments, creating a versatile and visually appealing ecosystem. By carefully planning and maintaining both the land and water components, you can enjoy a thriving, diverse habitat that brings a piece of nature into your home.

Fernery or fernerium

Fernery or fernerium

A collection of ferns in a terrarium is often referred to as a “fernery” or “fernerium.” These terms specifically describe a terrarium that is primarily dedicated to cultivating various species of ferns. Ferns thrive in humid environments, making them well-suited for terrariums where humidity and temperature can be controlled to create ideal growing conditions.

Creating a Fernery

If you are interested in setting up a fernery, here are some steps and tips to help you get started:

Choose a container that provides ample space for your ferns to grow. Glass containers, such as aquariums, glass jars, or specially designed terrariums, are ideal.

A lid helps maintain humidity, which is crucial for ferns. However, ensure there is some ventilation to prevent mold growth.

Add a layer of small pebbles or expanded clay pellets at the bottom to facilitate drainage and prevent waterlogging. Next add a thin layer of activated charcoal helps keep the terrarium fresh by absorbing odors and preventing mold.

Best to use a well-draining, organic-rich soil mix. A blend of potting soil, peat moss, and perlite works well for ferns.

Choose a variety of ferns that thrive in similar conditions. Some popular choices include Maidenhair Fern (Adiantum), Bird’s Nest Fern (Asplenium nidus), and Boston Fern (Nephrolepis exaltata). Arrange the ferns in the terrarium, ensuring they have enough space to grow. Plant taller ferns at the back and smaller ones at the front for a layered effect.

Maintain high humidity levels by misting the terrarium regularly. Using a humidity gauge can help you monitor the levels. Water the ferns regularly but avoid overwatering. The substrate should be moist but not soggy.

Positioning your creation, place the terrarium in a location with bright, indirect light. Avoid direct sunlight, which can overheat the terrarium and damage the ferns. 60-75°F (15-24°C) is an ideal temperature for most ferns

Trim dead or yellowing fronds to keep the terrarium looking neat and to prevent disease.

Inspect the ferns regularly for pests such as aphids or mites. If pests are found, treat them promptly with appropriate methods.

Feed the ferns with a diluted, balanced liquid fertilizer during the growing season, typically once a month. This will add lush greenery and a serene, natural beauty to any space. They are also known for their air-purifying properties, helping to improve indoor air quality. The presence of ferns can help increase humidity levels in the surrounding environment, which can be beneficial for other plants and your home’s overall air quality.

Creating a fernery allows you to enjoy the beauty and tranquillity of ferns within a controlled, miniature ecosystem. With proper care and maintenance, a fernery can be a stunning and low-maintenance addition to your home or office.

What is a Rainforest Terrarium?

A rainforest terrarium is a type of terrarium that replicates the lush, humid environment of a tropical rainforest. It typically includes a variety of tropical plants, a high level of humidity, and sometimes small animals such as reptiles, amphibians, or invertebrates. The goal is to create a self-sustaining ecosystem that mimics the conditions of a rainforest, providing a suitable habitat for the plants and animals that thrive in such an environment.

A rainforest terrarium is typically a closed system. This design is crucial for maintaining the high humidity levels and stable temperature conditions required by tropical plants and animals.

Key Features of a Rainforest Terrarium

High Humidity:

Maintains humidity levels between 70-90%.

Regular misting or an automated misting system is often used.

Tropical Plants:

Plants that thrive in humid, warm environments.

Examples include ferns, bromeliads, orchids, and mosses.

Warm Temperature:

Temperatures typically range from 75-85°F (24-29°C) during the day and slightly cooler at night.

Complex Substrate Layers:

A multi-layered substrate to support plant growth and water drainage.

Water Features (Optional):

Small ponds, waterfalls, or streams to enhance humidity and provide a water source for animals.

Natural Decor:

Use of natural materials like wood, rocks, and leaf litter to create a realistic environment.

How to Make a Rainforest Terrarium

Materials Needed

Terrarium Container: A glass or acrylic tank with a secure lid to maintain humidity.

Lighting: Full-spectrum LED or fluorescent lights suitable for plant growth.

Heating: Heat mats or lamps to maintain appropriate temperatures.

Substrate: A mix of organic soil, coconut coir, sphagnum moss, and drainage materials like expanded clay balls or gravel.

Plants: Tropical species like ferns, bromeliads, orchids, mosses, and small trees.

Water Features (Optional): Small pumps for creating waterfalls or ponds.

Decor: Natural items like branches, bark, rocks, and leaf litter.

Clean-Up Crew: Isopods and springtails to maintain soil health and manage waste.   See Clean Up Crew

Step-by-Step Guide to building a Rainforest Terrarium

1 Choose the Container:

Select a suitable terrarium tank. It should be large enough to accommodate the plants and any animals you plan to include.

2 Install the Drainage Layer:

Add a layer of expanded clay balls or gravel at the bottom for drainage.

Cover this layer with a mesh screen to prevent the substrate from mixing with the drainage layer.

3 Add the Substrate:

Prepare a substrate mix with organic soil, coconut coir, and sphagnum moss.

Add this mix on top of the mesh screen to a depth suitable for the plants’ root systems.

4 Set Up Water Features (Optional):

If including water features, position them before adding plants. Ensure the water feature components (like pumps) are properly installed and concealed.

5 Plant Selection and Arrangement:

Choose a variety of tropical plants that will thrive in the humid, warm environment.

Arrange the plants starting with larger ones at the back and smaller ones in the foreground. Ensure they are planted securely in the substrate.

6 Add Natural Décor:

Place branches, rocks, and pieces of bark to create a natural landscape.

Use these elements to provide hiding spots and climbing structures for any animals.

7 Introduce the Clean-Up Crew:

Add isopods and springtails to help break down organic matter and maintain soil health.

8 Install Lighting and Heating:

Set up full-spectrum lighting to provide adequate light for photosynthesis.

Install heating elements to maintain the desired temperature range.

9 Maintain Humidity:

Regularly mist the terrarium to maintain high humidity levels. Consider installing an automated misting system for convenience.

10 Monitor and Adjust:

Regularly check temperature and humidity levels to ensure they remain within the desired range.

Prune plants as needed and remove any dead material to prevent mold growth.


Creating a rainforest terrarium involves carefully replicating the conditions of a tropical rainforest within a controlled environment. By choosing the right plants, maintaining appropriate humidity and temperature, and incorporating a clean-up crew, you can create a thriving, self-sustaining ecosystem. This type of terrarium not only provides a suitable habitat for tropical plants and animals but also offers a beautiful, natural display for your home or office.

Sit back and enjoy your creation and watch it grow.

is the Rainforest Terrarium an open or closed system?

A rainforest terrarium is typically a closed system. This design is crucial for maintaining the high humidity levels and stable temperature conditions required by tropical plants and animals. Here’s why a closed system is ideal for a rainforest terrarium and the benefits it provides:

Characteristics of a Closed Rainforest Terrarium

High Humidity Retention:

The enclosed environment traps moisture, maintaining the high humidity levels necessary for tropical plants and animals.

Regular misting or an automated misting system helps to sustain this humidity.

Stable Temperature:

A closed terrarium helps to keep the temperature consistent, which is important for tropical species that require warm conditions.

Minimal Water Loss:

The sealed environment reduces evaporation, ensuring that water remains available for plants and the ecosystem.

Controlled Environment:

A closed system allows for better control over the internal climate, making it easier to maintain the ideal conditions for the terrarium’s inhabitants.

Benefits of a Closed Rainforest Terrarium

Enhanced Plant Growth:

Consistent humidity and temperature promote healthy plant growth, ensuring that tropical plants can thrive.

Reduced Maintenance:

The self-sustaining nature of a closed system means less frequent watering and maintenance, as the water cycle within the terrarium is largely self-contained.

Balanced Ecosystem:

The closed environment supports a balanced ecosystem where plants, microorganisms, and clean-up crew invertebrates interact naturally.

Natural Aesthetic:

The lush, dense plant growth in a closed terrarium creates a visually appealing and realistic representation of a rainforest.

Setting Up a Closed Rainforest Terrarium

Select a Suitable Container:

Choose a glass or acrylic tank with a secure lid to prevent moisture and heat from escaping.

Create a Drainage Layer:

Place a layer of expanded clay balls or gravel at the bottom to facilitate drainage and prevent waterlogging.

Add a Substrate Barrier:

Use a mesh screen to separate the drainage layer from the substrate.

Prepare the Substrate:

Mix organic soil, coconut coir, and sphagnum moss to create a nutrient-rich, well-draining substrate for plants.

Install Plants:

Choose tropical plants like ferns, bromeliads, orchids, and mosses. Arrange them in the substrate, ensuring they have enough space to grow.

Introduce a Clean-Up Crew:

Add isopods and springtails to help break down organic matter and keep the substrate healthy.

Set Up Lighting and Heating:

Use full-spectrum LED or fluorescent lights to provide the necessary light for plant growth.

Install heating elements if needed to maintain the desired temperature range.

Maintain Humidity:

Regularly mist the terrarium or use an automated misting system to maintain high humidity levels.

Monitor Conditions:

Keep an eye on temperature and humidity levels, adjusting as needed to ensure a stable environment.


A rainforest terrarium is best maintained as a closed system to replicate the high humidity and stable temperature conditions of a tropical rainforest. This setup supports the health and growth of tropical plants and can create a beautiful, self-sustaining miniature ecosystem. By carefully setting up and maintaining your closed rainforest terrarium, you can enjoy a thriving, natural environment right in your home.

What is a Bioactive Terrarium?

Bioactive Terrarium

A bioactive terrarium is an advanced type of terrarium that replicates a natural ecosystem. It includes not only plants and the main animals being kept, but also various microorganisms and “clean-up crew” invertebrates that help maintain the environment. This creates a self-sustaining system where waste is broken down and recycled, promoting a healthier and more natural habitat for the inhabitants.

Key Components of a Bioactive Terrarium

  1. Live Plants:
    • Essential for creating a natural environment, providing oxygen, and assisting in waste breakdown.
    • Examples: Tropical plants like ferns, pothos, and bromeliads for humid environments; succulents and cacti for arid setups.
    • Substrate Layers:
    • Drainage Layer: Often consists of clay balls or gravel to prevent waterlogging.
    • Barrier Layer: A mesh layer to separate the drainage layer from the substrate.
    • Substrate: A mix of organic soil, sand, and coconut fiber that supports plant growth and invertebrate life.
  2. Clean-Up Crew:
    • Includes decomposers such as springtails and isopods that break down waste and prevent mold and fungal growth.
    • These invertebrates consume organic matter, including feces and shed skin, converting it into nutrients for plants.
  3. Microfauna:
    • Tiny organisms like bacteria and fungi that contribute to nutrient cycling and soil health.
  4. Primary Inhabitants:
    • The main animals being kept, such as reptiles, amphibians, or invertebrates. The habitat is designed to meet their specific needs.

Benefits of a Bioactive Terrarium

  1. Natural Waste Breakdown:
    • Benefit: Clean-up crew organisms break down waste materials, reducing the need for frequent cleaning.
    • Advantage: Creates a healthier and more balanced environment for the inhabitants.
  2. Enhanced Plant Growth:
    • Benefit: Nutrient cycling from decomposed waste enriches the soil, promoting robust plant growth.
    • Advantage: Lush plant growth contributes to a more natural and visually appealing habitat.
  3. Improved Air Quality:
    • Benefit: Plants help to filter and oxygenate the air, improving air quality within the terrarium.
    • Advantage: This can benefit the health of the primary inhabitants.
  4. Stress Reduction for Inhabitants:
    • Benefit: A naturalistic environment with live plants and hiding spots reduces stress and encourages natural behaviors.
    • Advantage: Leads to healthier and more active animals.
  5. Educational Value:
    • Benefit: Demonstrates complex ecological interactions and the importance of biodiversity.
    • Advantage: Provides an engaging and educational experience for observers.
  6. Aesthetic Appeal:
    • Benefit: A bioactive terrarium with thriving plants and active clean-up crews creates a dynamic and visually appealing display.
    • Advantage: Enhances the visual enjoyment of the terrarium as a decorative piece.

Setting Up a Bioactive Terrarium

  1. Choose Appropriate Plants:
    • Select plants that match the humidity and light requirements of the primary inhabitants. For example, tropical plants for a rainforest setup, or succulents for a desert environment.
  2. Layer the Substrate:
    • Start with a drainage layer to prevent water buildup.
    • Add a mesh barrier to separate the drainage from the substrate.
    • Top with a bioactive substrate mix that supports plant growth and microfauna.
  3. Introduce the Clean-Up Crew:
    • Add springtails, isopods, and other beneficial invertebrates to help manage waste and keep the substrate healthy.
  4. Install Plants:
    • Plant a variety of species to create a natural and diverse environment. Ensure plants are rooted properly in the substrate.
  5. Add the Primary Inhabitants:
    • Once the plants and clean-up crew are established, introduce the main animals. Make sure the terrarium meets all their specific habitat needs.
  6. Monitor and Maintain:
    • Regularly check the health of plants and animals, maintain proper humidity and temperature levels, and add more clean-up crew organisms if necessary.


A bioactive terrarium is a self-sustaining, naturalistic enclosure that provides numerous benefits over traditional setups. It promotes a healthier environment through natural waste breakdown and nutrient cycling, enhances the well-being of the inhabitants by mimicking their natural habitat, and offers an aesthetically pleasing and educational display. By carefully setting up and maintaining a bioactive terrarium, you can create a thriving ecosystem that supports both plants and animals

Benefits of a Closed Terrarium

A closed terrarium is an enclosed environment that creates a self-sustaining ecosystem with its own microclimate. This type of terrarium is particularly suited for plants that thrive in high-humidity environments. Here are the benefits of a closed terrarium:

1. Self-Sustaining Ecosystem

  • Benefit: Closed terrariums can create a self-sustaining environment where water cycles naturally through condensation and evaporation.
  • Advantage: This minimizes the need for frequent watering, as the closed system recycles moisture.

2. High Humidity

  • Benefit: The enclosed space traps moisture, maintaining a consistently high humidity level.
  • Advantage: Ideal for tropical plants and humidity-loving species such as ferns, mosses, and orchids, which thrive in these conditions.

3. Stable Environment

  • Benefit: Closed terrariums provide a stable environment with less fluctuation in temperature and humidity.
  • Advantage: Beneficial for delicate plants that require consistent conditions to grow well.

4. Minimal Maintenance

  • Benefit: Once established, closed terrariums require minimal maintenance.
  • Advantage: The need for watering is significantly reduced due to the natural water cycle within the terrarium, making it easier to care for over time.

5. Educational Value

  • Benefit: Closed terrariums serve as excellent educational tools, demonstrating principles of ecology, the water cycle, and plant biology.
  • Advantage: They can be used to teach children and adults about ecosystems, sustainability, and plant care in a hands-on manner.

6. Aesthetic Appeal

  • Benefit: Closed terrariums create a lush, miniature landscape that can be very aesthetically pleasing.
  • Advantage: They can serve as attractive, low-maintenance decorative pieces for homes, offices, or public spaces.

7. Protection from Pests

  • Benefit: The enclosed environment protects the plants from common pests such as aphids and spider mites.
  • Advantage: Reduces the need for pest control measures and keeps the plants healthier.

8. Microclimate Control

  • Benefit: You can control the microclimate within a closed terrarium more easily than in an open environment.
  • Advantage: Allows for the cultivation of a diverse range of plants that may not thrive in the ambient conditions of a typical home.

9. Reduced Evaporation

  • Benefit: The enclosed system significantly reduces water evaporation.
  • Advantage: Conserves water and ensures plants have a consistent moisture supply, which is particularly beneficial in dry climates or for people who travel frequently.

10. Encourages Root Growth

  • Benefit: The humid environment promotes healthy root growth for many plant species.
  • Advantage: Plants with well-established root systems tend to be healthier and more resilient.

Ideal Plants for Closed Terrariums

  1. Ferns
    • Examples: Maidenhair fern, Boston fern.
    • Benefits: Thrive in high humidity and low light conditions.
  2. Mosses
    • Examples: Sheet moss, Cushion moss.
    • Benefits: Prefer constant moisture and high humidity.
  3. Orchids
    • Examples: Miniature orchids, Phalaenopsis.
    • Benefits: Appreciate the stable, humid environment.
  4. Peperomias
    • Examples: Peperomia obtusifolia, Peperomia caperata.
    • Benefits: Enjoy the humidity and grow well in low to moderate light.
  5. Pothos
    • Examples: Golden pothos, Marble queen.
    • Benefits: Tolerant of low light and high humidity, making them ideal for closed terrariums.
  6. Fittonia (Nerve Plant)
    • Examples: Fittonia albivenis.
    • Benefits: Requires high humidity and consistent moisture, and thrives in the conditions provided by closed terrariums.

Maintenance Tips for Closed Terrariums

  1. Watering:
    • Water sparingly. The goal is to keep the soil moist but not soggy. The closed system recycles water, so overwatering can lead to mold and root rot.
  2. Lighting:
    • Provide indirect light. Direct sunlight can cause overheating and condensation. LED grow lights can be used to supplement natural light if necessary.
  3. Ventilation:
    • Occasionally open the lid to allow fresh air exchange and prevent mold buildup. This can be done every few weeks.
  4. Pruning:
    • Regularly prune plants to prevent overcrowding and remove dead leaves to maintain a healthy environment.
  5. Cleaning:
    • Keep the glass clean to ensure adequate light penetration and maintain the aesthetic appeal.


Closed terrariums offer numerous benefits, particularly for plants that thrive in humid, stable environments. They require minimal maintenance, create a visually appealing display, and can serve as educational tools. By selecting the right plants and providing proper care, a closed terrarium can be a thriving, self-sustaining ecosystem that enhances any indoor space.

An Open Terrarium v Closed Terrarium

Open Terrarium

Open Terrarium
An open terrarium is a type of terrarium that features an open top, allowing for greater air circulation and less humidity compared to closed terrariums. These terrariums are particularly suited for plants and environments that thrive in drier conditions with good airflow.

Key Features:

Open Top: No lid or covering, providing free exchange of air with the surrounding environment.
Air Circulation: Enhanced airflow helps prevent excess moisture and mould growth.
Humidity Control: Naturally lower humidity levels, making it ideal for plants that prefer drier conditions.

Prevents Over-Humidity:
Benefit: Open terrariums reduce the risk of excess humidity, which can lead to mould, mildew, and fungal growth.
Advantage Over Closed: Closed terrariums can trap moisture, leading to overly humid conditions that are unsuitable for many plants.
Ideal for Dry-Climate Plants:
Benefit: Provides a suitable environment for succulents, cacti, and other xerophytes that thrive in dry conditions.
Advantage Over Closed: Closed terrariums typically create a humid environment, which can be detrimental to these types of plants.
Enhanced Air Circulation:
Benefit: Improved airflow helps to reduce stagnant air, promoting healthier plant growth and reducing the likelihood of pest infestations.
Advantage Over Closed: Closed terrariums can suffer from poor air circulation, which may lead to plant stress and disease.
Temperature Regulation:
Benefit: Open terrariums can better handle temperature fluctuations, as they allow heat to dissipate more easily.
Advantage Over Closed: Closed terrariums can trap heat, potentially leading to temperatures that are too high for some plants.
Ease of Maintenance:
Benefit: Easier to water and tend to plants without the need to remove a lid. Less concern about condensation and mold buildup.
Advantage Over Closed: Closed terrariums often require careful monitoring and adjustments to maintain appropriate humidity and prevent condensation issues.
Benefit: Open terrariums often have a more modern and sleek appearance, making them an attractive addition to home decor.
Advantage Over Closed: They can be styled more freely without the visual barrier of a lid, enhancing their visual appeal.
Examples: Echeveria, Haworthia, Aloe, and Sedum.
Benefits: These plants store water in their leaves, making them well-suited for the dry conditions of an open terrarium.
Examples: Mammillaria, Opuntia, and Rebutia.
Benefits: Cacti thrive in low-humidity environments and need good airflow to prevent rot.
Air Plants (Tillandsia):
Benefits: These plants can be placed in open terrariums to take advantage of the good airflow and minimal soil requirements.
Examples: Basil, Thyme, and Rosemary.
Benefits: Many herbs prefer dry conditions and good air circulation, making them suitable for open terrariums.
Water sparingly and ensure the soil dries out between waterings to prevent root rot.
Provide bright, indirect light. Succulents and cacti may need more direct sunlight.
Use well-draining soil mixes, such as cactus or succulent soil, to prevent waterlogging.
Regularly remove dead leaves and debris to prevent mould and pest issues.
Open terrariums offer several benefits over closed terrariums, especially for plants that thrive in dry, well-ventilated environments. They are easier to maintain, help prevent issues related to excess humidity, and can accommodate a variety of attractive, low-maintenance plants like succulents and cacti. This makes them an excellent choice for both novice and experienced plant enthusiasts looking to create a beautiful and sustainable plant display.