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Growing pothos above an aquarium is an easy way to add greenery to your fish tank while supporting a healthier aquatic environment. Its trailing vines create an attractive display above the water, while the roots develop into a natural-looking network beneath the surface. That's why many hobbyists like to keep them in aquariums. In this article, Splashy Fish will reveal everything you need to know to keep your Pothos thriving in aquarium tank.
Can Pothos Grow in Aquarium?
Pothos, scientifically known as Epipremnum aureum, is a hardy tropical houseplant also commonly called golden pothos or devil’s ivy. It adapts well to indoor conditions and can grow roots directly in water, making it a popular choice for open-top aquariums, hang-on-back filters, and planted fish tank displays.
As pothos grows, its roots absorb nitrogen compounds such as ammonium and nitrate, along with other nutrients from the aquarium water. This may help slow nitrate accumulation and reduce some of the excess nutrients available to algae.
However, pothos is not a true aquatic plant. Its roots can remain submerged, but the leaves and most of the stem must grow above the water. Pothos should also be treated as an additional form of nutrient support rather than a replacement for an aquarium filter, regular water testing, or routine water changes.
Benefits of Growing Pothos in an Aquarium
Helps Manage Nitrate Naturally
Fish waste, uneaten food, and decaying organic material release ammonia into aquarium water. Beneficial microorganisms convert ammonia into nitrite and then into nitrate as part of the aquarium nitrogen cycle.
Nitrate is less immediately harmful than ammonia or nitrite, but it can accumulate over time in a closed aquarium. Growing plants use nitrogen compounds to produce new roots, stems, and leaves.
A mature pothos with a healthy root system may absorb some of the nitrogen available in the water. This can help slow nitrate accumulation between aquarium water changes, especially in tanks with a moderate or heavy bioload.
The effect is gradual. One small cutting will not immediately correct dangerously high nitrate. The amount absorbed depends on:
- Plant size
- Root development
- Available light
- Aquarium volume
- Fish stocking level
- Feeding habits
- Water chemistry
- Overall plant growth
Continue monitoring nitrate with a reliable aquarium water test kit. Do not judge water quality only by how healthy the pothos appears.
Provides Cover for Fish and Shrimp
Once established, pothos can develop long, branching roots beneath the water surface. These roots create a natural structure that small fish, fry, shrimp, and shy aquarium inhabitants may use for cover.
The root surfaces can also support biofilm and microorganisms. Freshwater shrimp may graze around the root system while searching for tiny food particles.
Check the roots regularly because dense root growth may also trap uneaten food, fish waste, and plant debris.
May Help Limit Excess Algae
Pothos and algae both depend on nutrients in the aquarium water. When a pothos plant is actively growing, it may use some of the nutrients that would otherwise remain available to algae.
This does not make pothos an instant algae treatment. Algae can still develop because of:
- Excessively long lighting periods
- Direct sunlight
- Overfeeding
- Poor circulation
- Accumulated organic waste
- Unstable carbon dioxide
- Infrequent aquarium maintenance
Use pothos as part of a balanced aquarium care routine rather than as a cure for every algae problem.
Adds Greenery Without Planting the Substrate
Pothos is especially helpful in fish tanks where submerged plants are frequently uprooted, damaged, or eaten.
The leaves remain outside the aquarium, while only the roots are exposed to the livestock. This makes pothos useful in some Goldfish, Cichlid, Livebearer, community, and shrimp tanks when the roots can be protected appropriately.
What Pothos Cannot Do
Although pothos can support aquarium water quality, it does not perform every function of a conventional filter.
Pothos cannot mechanically capture suspended debris, fish waste, or uneaten food in the same way that filter foam, floss, or other mechanical media can.
It also does not provide controlled water circulation. Your aquarium still needs a correctly sized filter to:
- Move water through the tank
- Trap visible debris
- Support beneficial microorganisms
- Improve gas exchange
- Maintain more consistent water conditions
Pothos also does not eliminate the need for water changes. Even when nitrate remains low, other dissolved compounds may accumulate while essential minerals become depleted.
Continue performing partial water changes based on test results, stocking level, feeding, and the needs of the livestock.
Should You Start With a Cutting or a Potted Plant?
Starting With a Pothos Cutting
A fresh pothos cutting is often easier to prepare because there is less soil, fertilizer residue, and root material to remove.
Select a healthy section of vine containing at least one node. The node is the slightly swollen area where a leaf and an aerial root may emerge from the stem. New roots develop from this area.
Use clean scissors to cut the stem just below the node. Remove any leaf that would otherwise remain underwater.
Position the cutting so that:
- At least one node touches the aquarium water.
- The leaves remain above the surface.
- The stem is held securely.
- The cutting cannot fall completely into the tank.
A cutting may take several weeks to produce a strong root system. During this period, inspect it for soft, blackened, or foul-smelling stem tissue.
Using a Potted Pothos Plant
A small potted pothos provides faster visual impact because it already has established leaves and roots. However, it requires more preparation before it can be placed near aquarium livestock.
Remove the plant from its pot and gently separate the root mass into smaller sections. Rinse the roots repeatedly in clean water until all visible potting soil has been removed.
Pay close attention to:
- Soil trapped near the center of the roots
- Slow-release fertilizer beads
- Pesticide residue
- Leaf-shine products
- Damaged or rotting roots
- Plant pests
Do not introduce potting soil or terrestrial fertilizer into a stocked fish tank.
After cleaning the roots, keep the nursery-grown pothos in a separate container of conditioned water for several days. Replace the water regularly and continue inspecting the plant for soil residue, pests, or signs of chemical treatment.
This extra precaution is particularly important before placing pothos in aquariums containing freshwater shrimp or snails.
How to Place Pothos in an Aquarium
The most important rule is simple: keep the roots wet and the leaves dry.
Pothos can be positioned in several ways depending on the aquarium design.
Attach It to the Aquarium Rim
One of the easiest methods is to secure the plant along the back or side of the fish tank.
Place the roots and at least one healthy node in the water while allowing the leaves and vine to remain above the surface.
Possible holders include:
- Aquarium plant clips
- Suction-cup holders
- Breeder-box brackets
- Suspended baskets
- Aquarium-safe plant holders
Make sure the holder does not crush the stem or restrict future root development.
A rim-mounted setup makes it easy to examine and trim the roots. It also helps keep them away from filter motors and moving equipment.
Grow It Inside a Hang-on-Back Filter
Pothos may also be placed in the media compartment of a hang-on-back filter. This provides the roots with continuous access to flowing, oxygenated aquarium water.
Keep the roots away from:
- The impeller
- The motor compartment
- The intake assembly
- Essential filter media
- Narrow water outlets
Pothos roots can grow quickly and may eventually reduce filter flow or interfere with the impeller. Check and trim them regularly before they reach moving parts.
Do not remove important biological media just to make room for the plant. Pothos should complement the aquarium filter rather than reduce its filtration capacity.
Use a Rear Chamber or Suspended Basket
Aquariums with built-in rear filtration compartments may support pothos above one of the chambers, provided the roots cannot reach the pump.
A suspended basket can also hold the plant securely while allowing the roots to grow downward into the aquarium.
Do not fill the basket with regular potting soil. The pothos should obtain nutrients through its submerged roots rather than from loose terrestrial substrate.
Why Pothos Leaves Must Stay Above Water?
Pothos is a terrestrial vine, not a fully aquatic stem plant.
Its roots can adapt to permanent submersion, but its leaves are designed to exchange gases in the air. Keeping the foliage underwater can eventually cause:
- Yellow leaves
- Soft or transparent tissue
- Leaf decay
- Stem rot
- Increased organic waste in the aquarium
A leaf that is accidentally submerged for a short period will not necessarily destroy the plant. However, the leaves and most of the stem should not remain underwater continuously.
Position the plant so that:
- The roots stay submerged.
- One or more nodes contact the water.
- All healthy leaves remain above the surface.
- The vine cannot slide into the tank.
- Condensation does not keep the leaves constantly wet.
When using a partially open aquarium lid, check that the opening does not allow jumping fish, snails, shrimp, or other livestock to escape.
What to Expect During the First Month
A newly added pothos may not begin growing immediately. The plant often needs time to adjust to its new environment.
Soil-grown roots and water-grown roots are structurally different. Some fine roots from a potted plant may decline after being permanently submerged.
Remove roots that become:
- Dark brown or black
- Soft or slimy
- Hollow
- Foul-smelling
- Easily detached
Healthy new water roots are usually white, cream, or light tan. They should feel firm rather than mushy.
Over the following weeks, new root tips may begin extending into the tank. A cutting may also produce a new leaf from its growing point.
The speed of growth depends on:
- Light intensity
- Plant condition
- Water temperature
- Available nutrients
- Root health
- Room temperature
Avoid adding large amounts of fertilizer simply to force faster pothos growth. Unnecessary nutrients may contribute to algae or disrupt the balance of the planted aquarium.
Continue testing nitrate before and after routine water changes. A simple record can help you determine whether nitrate accumulation changes as the pothos develops.
Lighting Requirements for Aquarium Pothos
Pothos can tolerate relatively low indoor light, but it still needs enough light to maintain healthy growth.
Bright indirect light generally produces stronger roots, larger leaves, and more compact growth. In very low light, the plant may survive but grow slowly, lose variegation, or develop long spaces between leaves.
The aquarium light may be sufficient when the pothos grows directly beside or above it. However, aquarium lights are usually directed downward toward the fish tank rather than outward toward terrestrial foliage.
A small houseplant grow light may help when the leaves receive little ambient light.
Avoid placing the aquarium and pothos in intense direct sunlight. Strong afternoon sunlight may:
- Burn pothos leaves
- Heat the aquarium
- Increase evaporation
- Encourage algae growth
Variegated pothos varieties often require more light than solid-green varieties because the pale areas of their leaves contain less chlorophyll.
Pothos Aquarium Maintenance
Pothos is relatively easy to maintain once established. Most care can be completed during routine aquarium maintenance.
Inspect the Leaves
Check for yellowing, brown spots, pests, or physical damage. Remove dying leaves before they fall into the fish tank.
Cut the leaf stem near the vine with clean scissors rather than pulling it away.
Examine the Roots
Lift the root mass carefully and look for trapped debris, dead roots, or excess organic material.
When necessary, gently swish the roots in aquarium water removed during a water change. Avoid rinsing them aggressively under untreated tap water.
Trim Excessive Root Growth
Pothos roots may need trimming when they:
- Enter the filter motor
- Reduce water flow
- Fill too much swimming space
- Trap excessive debris
- Interfere with aquarium maintenance
Use clean scissors and remove only part of the root mass at one time. Severe trimming may temporarily slow plant growth.
Prune and Train the Vine
Long vines can be guided along a shelf, wall, aquarium stand, or small trellis.
Pruning the vine may encourage fuller growth. Healthy sections containing a node can be propagated into new plants.
Common Pothos Aquarium Problems
Yellow Pothos Leaves
An occasional older yellow leaf may be normal. Frequent yellowing can indicate:
- Inadequate light
- Excessive direct sunlight
- Root damage
- Submerged foliage
- Stem rot
- Nutrient imbalance
- Pest activity
Inspect both the foliage and roots before adding fertilizer. Do not assume every yellow leaf is caused by a nutrient deficiency.
Brown or Mushy Roots
Some soil-grown roots may deteriorate after being transferred to water. Remove damaged portions while preserving firm, healthy roots.
Root decay may also occur when:
- Debris collects around the base.
- Too much stem remains underwater.
- Water circulation is poor.
- Rotting leaves are left attached.
- The plant was damaged before placement.
No New Growth
A newly transferred cutting may spend several weeks producing roots before creating new leaves.
Slow growth may also result from:
- Insufficient light
- Low room temperature
- Poor root health
- Repeated repositioning
- Very low nutrient availability
Give a healthy cutting time to establish before making major changes.
Roots Clogging the Filter
Inspect pothos growing inside a hang-on-back filter frequently. Redirect or trim the roots before they enter the impeller compartment.
Move the plant to a rim-mounted holder when root growth repeatedly interferes with filter operation.
Fish Damaging the Roots
Many community fish ignore pothos roots, but some fish may bite, pull, or uproot them.
Large cichlids, goldfish, and other strong or curious species may require the roots to be placed behind a divider or inside a protected filter compartment.
Is Pothos Safe Around Cats and Dogs?
Pothos contains insoluble calcium oxalate crystals. Chewing or swallowing the plant can cause oral irritation in cats and dogs.
Possible symptoms include:
- Drooling
- Pawing at the mouth
- Vomiting
- Oral pain
- Difficulty swallowing
Keep pothos vines, leaves, and pruned plant material out of reach of pets and small children.
Cats may still reach a vine growing above a tall aquarium, especially when it trails across nearby furniture. Secure the plant carefully and remove fallen leaves immediately.
Which Aquariums Are Suitable for Pothos?
Pothos can work well in many freshwater setups, including:
- Community fish tanks
- Betta aquariums
- Guppy and livebearer tanks
- Shrimp aquariums
- Breeding and grow-out tanks
- Heavily stocked freshwater tanks
- Open-top planted aquariums
- Goldfish systems with protected roots
It may be less suitable when:
- The aquarium must remain fully covered.
- The room receives extremely poor light.
- Fish repeatedly destroy the roots.
- The roots cannot be kept away from the filter motor.
- Cats or dogs can easily reach the leaves.
- The plant cannot be secured above the surface.
Conclusion
Growing pothos in an aquarium is a simple way to add attractive greenery above the tank while supporting natural nutrient uptake below the surface.
Its roots may absorb ammonium, nitrate, and other nutrients as the plant grows. The root system can also provide cover for small fish, fry, and freshwater shrimp.
For the best results, clean nursery-grown roots thoroughly, keep the leaves above water, provide bright indirect light, and trim the roots before they interfere with filtration.
Most importantly, use pothos as a supplement to responsible aquarium care. Continue operating a suitable filter, testing ammonia, nitrite, and nitrate, and performing partial water changes according to the needs of the aquarium.
While pothos is not a true aquatic plant, it can be paired with submerged and floating species to create a fuller, more natural display. Explore Splashy Fish’s selection of live aquarium plants, aquarium filters, and water testing kits to support a healthier freshwater aquarium.
Frequently Asked Questions (FAQs)
Can pothos live fully submerged in a fish tank?
No. Pothos is a terrestrial tropical vine rather than a true aquatic plant. Its roots and one or more nodes can grow in aquarium water, but the leaves and most of the stem should remain above the surface. Permanently submerged foliage may yellow, decay, and release organic material into the aquarium.
How much pothos do I need to reduce nitrate in an aquarium?
There is no fixed number of pothos cuttings suitable for every aquarium. Nitrate uptake depends on plant size, root mass, lighting, growth rate, aquarium volume, feeding, and stocking level. Start with one or several healthy cuttings and monitor nitrate with a water test kit. Continue normal water changes based on test results rather than the number of plants.
Can pothos replace an aquarium filter and water changes?
No. Pothos may absorb nitrogen compounds and help slow nitrate accumulation, but it cannot remove solid waste, create reliable water circulation, or replace mechanical and biological filtration. Continue using a properly sized aquarium filter, testing the water, removing debris, and performing partial water changes.
