Can You Put Devils Ivy in a Fish Tank? - Plant Care Guide

Yes, you can put Devil's Ivy (Epipremnum aureum, commonly known as Pothos) in a fish tank, but it's crucial to understand that only the roots should be submerged in the water, while the foliage must remain outside the tank. This popular houseplant is remarkably effective at absorbing nitrates and other waste products from aquarium water, benefiting fish health and water quality, but its leaves are toxic if ingested by aquatic inhabitants.

Why is Devil's Ivy a Good Plant for Aquariums (with Precautions)?

Devil's Ivy (Epipremnum aureum), also known as Pothos, is considered a good plant for aquariums (with specific precautions) primarily because of its exceptional ability to absorb nitrates and other harmful waste products directly from the water. This natural filtration process significantly improves water quality, benefiting fish health, reducing algae growth, and minimizing the frequency of water changes. However, its foliage is toxic, necessitating careful placement.

Here's why Devil's Ivy is a beneficial addition to an aquarium system:

• Nitrate Absorption (Powerful Filtration):

  • The Main Benefit: Fish waste and decaying food break down into ammonia, then nitrites, and finally nitrates. High nitrate levels are harmful to fish and encourage algae growth. Devil's Ivy is a nitrate powerhouse; its extensive root system efficiently pulls nitrates directly from the water.
  • Improved Water Quality: This natural filtration dramatically lowers nitrate levels, creating a healthier, less stressful environment for fish and other aquatic life. An aquarium test kit will show significant nitrate reduction.
  • Reduced Algae: By consuming nitrates, Devil's Ivy starves nuisance algae of their primary food source, helping to keep the tank cleaner and clearer.
  • Fewer Water Changes: With lower nitrate levels, you may be able to reduce the frequency or volume of your regular water changes, saving time and effort.

• Ease of Growth:

  • Hardy and Adaptable: Devil's Ivy is an incredibly resilient and easy-to-grow plant. It thrives in various conditions, making it an ideal candidate for aquarium filtration. It roots readily in water.
  • Minimal Maintenance: Once established, it requires very little maintenance within the aquarium setting.

• Oxygenation (Minor Benefit):

  • While its primary benefit is nitrate absorption, any living plant undergoing photosynthesis contributes some oxygen to the water, though this is usually minor compared to mechanical aeration.

• Aesthetic Appeal:

  • Natural Decoration: The trailing vines and lush foliage of Devil's Ivy growing out of the top of the tank add a beautiful, natural, and vibrant touch to your aquarium setup, blending it seamlessly into your home decor. It creates a "jungle" or "riparium" look.

• Toxicity Precaution (Crucial):

  • Leaves are Toxic: The critical caveat is that Devil's Ivy leaves contain calcium oxalate crystals, which are toxic if ingested.
  • Placement: Therefore, only the roots should be submerged in the aquarium water, while all foliage must remain outside the tank to prevent fish or other aquatic animals from nibbling on the leaves.

By carefully integrating Devil's Ivy into your aquarium, you can leverage its powerful natural filtration capabilities to create a healthier and more beautiful aquatic environment, provided strict precautions are taken regarding its foliage.

What Parts of Devil's Ivy Can Go in a Fish Tank?

Only the roots and root structure of Devil's Ivy can safely go in a fish tank, while all foliage, stems, and leaves must remain entirely outside the aquarium water. This strict separation is crucial because the leaves and stems contain toxic compounds that can harm or kill fish if ingested, while the submerged roots offer significant benefits to water quality.

Here's a breakdown of the parts and their placement:

• Roots (Submerged - Recommended):

  • Function: The roots are the workhorses. When submerged, they grow extensively into the aquarium water and are responsible for absorbing nitrates, phosphates, and other waste products directly from the water column.
  • Appearance: They will develop a healthy, often white or creamy, network within the tank, providing a natural aesthetic.
  • Safety: The roots themselves are non-toxic when submerged and pose no threat to fish.

• Stems (Should NOT be Submerged - Use as "Bridge"):

  • Function: Stems are typically used as a bridge to get the roots into the water while keeping the leaves out.
  • Placement: Only the cut end of a stem that will develop roots should initially be placed in the water. As roots form, the stem portion with leaves should always be above the waterline.
  • Toxicity: Stems also contain the toxic calcium oxalate crystals. If submerged for extended periods, decaying stems can release these toxins into the water, and if fish nibble on them, it can cause harm.

• Leaves/Foliage (Must Stay OUT of the Water - Critical):

  • Function: The leaves are the primary photosynthetic organs, but their contact with aquarium water is a major hazard.
  • Toxicity: Devil's Ivy leaves contain calcium oxalate crystals, which are a known irritant and toxic if consumed. If leaves fall into the water and are eaten by fish, or if they decay and leach toxins, they can cause gill irritation, digestive upset, swelling, and potentially death in fish.
  • Placement: Absolutely ensure all green leaves are above the waterline and cannot fall into the tank. You may need to trim off any lower leaves that are close to the water before positioning the plant.

How to Position Devil's Ivy:

The common method is to use a cutting of Devil's Ivy with a few nodes (where leaves used to be or where new roots emerge). Place the cut end into the water, ensuring the remaining leaves are securely positioned above the water line. You can use clips, suction cups, or a small plant holder designed for aquariums to achieve this.

In summary: Roots in, leaves out. This simple rule ensures you harness the beneficial filtration properties of Devil's Ivy without exposing your aquatic inhabitants to its toxic foliage.

How Do You Prepare Devil's Ivy for a Fish Tank?

Preparing Devil's Ivy for a fish tank involves taking cuttings, carefully removing lower foliage, and ensuring the plant is clean and free of contaminants before introducing its roots to the aquarium water. Proper preparation is essential to prevent introducing harmful substances into your tank and to ensure the plant thrives in its new aquatic environment.

Here's a step-by-step guide to preparing Devil's Ivy for your fish tank:

1. Select Healthy Cuttings:

   • Source: Choose healthy, vigorous stems from an existing Devil's Ivy plant.
   • Length: Aim for cuttings that are 6-12 inches long and have several leaf nodes (the bumps on the stem where leaves or roots grow) along their length.
   • Avoid: Do not use cuttings that show signs of disease, pests, or yellowing leaves.

2. Make Clean Cuts:

   • Tools: Use sharp, clean scissors or pruning shears. Sterilize them with rubbing alcohol before and after use to prevent spreading diseases.
   • Cut Location: Make a clean cut on the stem just below a leaf node. Roots will emerge most readily from these nodes.

3. Remove Lower Leaves (Crucial Step):

   • Toxicity & Decay: This is perhaps the most important step for safety. Remove all leaves from the lower portion of the cutting that will be submerged in the aquarium water. Leaves contain toxic compounds and will also rot if submerged, releasing harmful substances into the tank.
   • Action: Leave only 2-3 leaves at the very top of the cutting, ensuring they will remain well above the waterline once positioned in the tank.

4. Rinse Thoroughly (and Optionally Soak):

   • Remove Contaminants: Rinse the entire cutting, especially the stem and any remaining leaves, under cool running water. This removes dust, dirt, spider mites, and any potential pesticide residues that might be on the plant from its previous environment.
   • Optional Soaking: Some aquarists recommend soaking the cutting in dechlorinated water for a few hours (or even overnight) to ensure any residues are fully leached out before introduction to the tank.

5. Allow for Callusing (Optional but Recommended):

   • Purpose: For cuttings that will be fully submerged (like setting directly into filter compartments), allowing the cut end to "callus" can help prevent rot.
   • Method: Place the cuttings in a dry, well-ventilated spot for 1-2 days until the cut end forms a dry, protective layer. This is less critical if only a small part of the stem is submerged and quickly forms roots.

6. Initial Rooting (Optional, but Expedites Process):

   • While Devil's Ivy will root directly in aquarium water, you can expedite the process by pre-rooting cuttings in a separate jar of dechlorinated water for 1-2 weeks. This gives them a head start before committing them to the tank. You can use an aquarium dechlorinator for this.

Once prepared, your Devil's Ivy cuttings are ready to be safely introduced to your fish tank, with all foliage remaining above the waterline, to begin their beneficial work of natural filtration.

Where is the Best Place to Put Devil's Ivy in a Fish Tank?

The best place to put Devil's Ivy in a fish tank is where its roots can be fully submerged in the water for nutrient absorption while its foliage remains completely outside the tank. Strategic placement also considers optimal light exposure for the plant and minimal disturbance to aquatic life. The most common and effective locations are on the rim of the tank, within filter compartments, or by using specialized plant holders.

Here are the best placement options for Devil's Ivy in a fish tank:

1. Draped Over the Tank Rim:

   • Method: This is the simplest and most common method. The cutting's stem is simply draped over the edge of the aquarium, with the leafless portion submerged in the water and the leafy portion hanging outside.
   • Benefits: Very easy to install and remove. Allows for maximum light exposure to the foliage. Minimal disturbance to the tank interior.
   • Securing: You might use a small piece of tape, a twist tie, or a plastic plant clip for aquariums to hold the stem securely in place on the rim.

2. Within Filter Compartments (Hang-on-Back Filters):

   • Method: For hang-on-back (HOB) filters, you can often place the prepared Devil's Ivy cuttings directly into the filter's media basket or overflow compartment, allowing the roots to grow within the filter's flow.
   • Benefits: Excellent for nitrate absorption as the roots are constantly exposed to nutrient-rich, circulating water. Keeps roots out of the main display tank if desired. Provides light to foliage (if compartment is open).
   • Considerations: Ensure the roots don't clog the filter impeller. May require periodic trimming of roots inside the filter.

3. Using Suction Cup Plant Holders:

   • Method: Attach a small aquarium suction cup plant holder to the inside glass near the waterline. Place the leafless stem cutting into the holder.
   • Benefits: Keeps the plant neatly organized and off the tank rim. Aesthetically pleasing.
   • Considerations: Ensure the suction cup is strong enough to hold the growing plant.

4. Integrated into a Riparium Setup:

   • Method: For more advanced setups, you can build a riparium where a portion of the tank is dedicated to emergent plants. This might involve creating a "false bottom" with inert media (like clay balls) or specialized baskets where the Devil's Ivy roots can grow, and the plant grows upwards out of the water.
   • Benefits: Highly aesthetic, excellent filtration, creates a natural transition from aquatic to terrestrial environments.
   • Considerations: Requires more planning and setup.

Important Placement Considerations:

• Foliage Above Water: Reiterate: ALL leaves must remain above the waterline to prevent toxicity to fish and to avoid leaf decay in the water.
• Light for Foliage: Position the foliage where it receives adequate light (bright indirect light is usually sufficient for Devil's Ivy). If the leaves are in a dark spot, the plant won't thrive, and its filtration capabilities will be reduced.
• Fish Interaction: Ensure the roots don't interfere with fish swimming space or filter intake. Observe fish behavior; some fish might nip at roots, though Devil's Ivy roots are usually safe.
• Maintenance Access: Place the plant in a location that still allows for easy access for tank cleaning and plant maintenance (e.g., trimming roots).

By choosing one of these optimal placement strategies, you can safely integrate Devil's Ivy into your aquarium, maximizing its benefits for water quality while maintaining a beautiful and healthy environment for your fish.

How Do I Care for Devil's Ivy in a Fish Tank Setup?

Caring for Devil's Ivy in a fish tank setup is remarkably low-maintenance due to the plant's hardy nature and the aquatic environment providing consistent moisture and nutrients. The primary care involves occasional root trimming, ensuring adequate light for the foliage, and regular monitoring for overall plant and tank health.

Here’s a guide to maintaining your Devil's Ivy in an aquarium setup:

1. Light for Foliage (Essential):

   • Requirement: The leaves of the Devil's Ivy that are outside the tank still need light for photosynthesis. Bright, indirect light is usually sufficient, but a few hours of direct morning sun can also be beneficial.
   • Placement: Position the tank or the plant's foliage near a window (avoiding intense, scorching afternoon sun) or under dedicated aquarium lights or general grow lights.
   • Consequence of Low Light: Insufficient light will cause the leaves to yellow, growth to slow, and the plant's nitrate-absorbing capabilities to diminish.

2. Root Trimming (As Needed):

   • Vigorous Growth: Devil's Ivy roots grow very rapidly and can become extensive within the aquarium, potentially filling up filter compartments or taking up too much swimming space for fish.
   • Method: Periodically, gently pull the cutting(s) out of the water and use clean scissors to trim back excess roots. Trim by no more than one-third at a time.
   • Frequency: This may be needed every few weeks to months, depending on growth rate.
   • Caution: Avoid excessive trimming, as the roots are the primary nitrate absorption system.

3. Monitor Water Quality (Especially Nitrates):

   • Observe Effectiveness: While Devil's Ivy is excellent at absorbing nitrates, it's still good practice to monitor your aquarium's water parameters regularly using an aquarium test kit. This confirms the plant's effectiveness and helps you gauge if your regular water changes can be reduced.
   • Signs of Overload: If nitrate levels remain high, you might need more Devil's Ivy cuttings, or your tank's bioload is too high for the current plant filtration.

4. Monitor Foliage Health:

   • Yellowing Leaves (Above Water): Yellowing leaves outside the tank usually indicate a lack of sufficient light or, less commonly, a nutrient deficiency (which is rare as they get nutrients from the tank).
   • Dust: Wipe dust off the leaves with a damp cloth to maximize photosynthesis.
   • Pests: Inspect leaves for common houseplant pests like spider mites or aphids. If found, treat outside the tank with an appropriate organic spray (like insecticidal soap), ensuring none of it gets into the aquarium water.

5. Fertilization (Not Required - from Aquarium Water):

   • Self-Sustaining: The Devil's Ivy gets all the nutrients it needs (especially nitrogen and phosphates) directly from the aquarium water via the fish waste and decaying organic matter. You should never fertilize the plant directly if its roots are in the fish tank, as this could introduce harmful chemicals to your aquatic environment.

6. Replenish Cuttings (If Needed):

   • Over time, older cuttings might become less vigorous. If you notice a significant slowdown in growth or increased yellowing, you can easily take new cuttings and replace the older ones.

By following these simple care guidelines, your Devil's Ivy will flourish in its unique aquarium role, providing continuous natural filtration and a beautiful aesthetic with minimal effort.

What Are the Benefits for the Fish Tank Environment?

Integrating Devil's Ivy into a fish tank environment offers a range of significant benefits that directly contribute to healthier fish, improved water quality, and a more stable, natural ecosystem within the aquarium. These advantages leverage the plant's powerful natural filtration capabilities, creating a more balanced and thriving aquatic habitat.

Here are the key benefits for the fish tank environment:

1. Superior Nitrate Reduction (Primary Benefit):

   • Waste Removal: Devil's Ivy roots are incredibly efficient at absorbing nitrates, the end product of the nitrogen cycle (fish waste, decaying food). High nitrates are toxic to fish and a primary cause of stress and disease.
   • Healthier Fish: Lower nitrate levels mean healthier, less stressed fish, with stronger immune systems and better vibrant colors.
   • Reduced Algae Growth: Nitrates are also a major food source for nuisance algae. By consuming these nitrates, Devil's Ivy effectively starves the algae, leading to clearer water and less frequent tank scrubbing.

2. Phosphate Absorption:

   • Beyond nitrates, Devil's Ivy roots also absorb phosphates, another nutrient that contributes to algae growth. This provides an additional layer of natural algae control.

3. Fewer Water Changes:

   • With the plant actively removing nitrates and phosphates, the rate at which these undesirable compounds accumulate is significantly slowed. This often means aquarists can reduce the frequency or volume of their regular water changes, saving time, effort, and resources.

4. Stabilization of Water Parameters:

   • Active plant growth helps to stabilize the overall chemistry of the aquarium water, contributing to a more balanced and resilient ecosystem. This can include minor buffering effects and removal of other dissolved organic compounds.

5. Natural Aesthetic and Enrichment:

   • Riparian Look: The trailing foliage of Devil's Ivy outside the tank creates a beautiful "riparian" or "jungle" aesthetic, blurring the line between the aquatic and terrestrial environments.
   • Fish Enrichment: While not directly interacting with the roots, the presence of plant roots can provide some visual enrichment and sense of security for certain fish species within the tank.

6. Detoxification (Minor):

   • Plants can sometimes absorb minor amounts of other dissolved toxins or heavy metals from the water, acting as a living bioremediation system, though this is less significant than nitrate removal.

7. Cost-Effective and Sustainable:

   • Using Devil's Ivy for filtration is a cost-effective alternative or supplement to expensive chemical filtration media. It's also a sustainable and environmentally friendly approach to aquarium management.

By harnessing the natural power of Devil's Ivy, aquarists can create a cleaner, healthier, and more aesthetically pleasing fish tank environment, promoting the well-being of their aquatic inhabitants with minimal ongoing effort.

What Are the Potential Downsides or Risks?

While using Devil's Ivy in a fish tank setup offers many benefits, it's important to be aware of potential downsides or risks to ensure the safety of your aquatic environment and the health of your plants. These risks primarily revolve around the plant's toxicity if improperly placed, and the need for ongoing vigilance.

Here are the potential downsides or risks:

1. Toxicity to Fish (If Foliage Submerged or Ingested):

   • Primary Risk: The most significant danger is that Devil's Ivy leaves and stems contain calcium oxalate crystals. If these parts are submerged in the water, they can rot and leach toxins, or if fish (especially herbivorous or curious ones) nibble on fallen leaves, it can cause:
     • Irritation: Burning or irritation of gills, mouth, and digestive tract.
     • Swelling: Swelling of mouth and throat.
     • Gastrointestinal Distress: Vomiting or digestive upset.
     • Mortality: In severe cases, especially with high ingestion or prolonged leaching, it can be fatal to fish.
   • Mitigation: This risk is entirely preventable by ensuring all foliage remains outside the tank.

2. Root Overgrowth and Clogging:

   • Vigorous Growth: Devil's Ivy roots grow rapidly and extensively in nutrient-rich aquarium water.
   • Clogging Filters: If placed in filter compartments, roots can become so dense that they clog the filter's intake or impeller, impeding water flow and reducing filtration efficiency.
   • Reduced Swimming Space: In the main tank, an overly dense root mass can reduce swimming space for fish or make it difficult for you to perform maintenance.
   • Mitigation: Regular root trimming is essential.

3. Potential for Nutrient Depletion (Less Common for Fish Tanks):

   • While Devil's Ivy efficiently absorbs nitrates, in a very lightly stocked tank with minimal waste, it could theoretically compete with submerged aquatic plants for other trace nutrients, or even deplete nitrates too much.
   • Mitigation: This is rarely an issue in a typical fish tank with fish waste as a nutrient source. Monitor water parameters.

4. Introduction of Pests/Diseases (If Not Cleaned):

   • If cuttings are taken from a plant that had houseplant pests (like spider mites or fungus gnats), these could potentially be introduced to the tank environment or spread to other houseplants, if not thoroughly rinsed prior to placement.
   • Mitigation: Always thoroughly rinse and inspect cuttings.

5. Mess and Maintenance (Minor):

   • Falling Leaves: If not properly secured, leaves might fall into the tank.
   • Root Trimming: Requires occasional attention to prune roots.
   • Foliage Care: The terrestrial part of the plant still needs adequate light and occasional cleaning (dusting).

6. Not Suitable for All Tank Setups:

   • Aggressive Fish: Tanks with fish known to jump or aggressively pull at roots might not be ideal.
   • No Place for Roots: Not all tank lids or filter setups easily accommodate emergent plant roots.

By being mindful of these potential downsides and implementing the necessary precautions and maintenance routines, you can largely mitigate the risks and enjoy the numerous benefits of using Devil's Ivy for aquarium filtration.