Can I Put Pothos in My Fish Tank? Safe Tips & Benefits

By James Wilson · January 24, 2026

Can I Put Pothos in My Fish Tank?

Yes, you can safely grow pothos (Epipremnum aureum) with your fish tank, but the plant should not be fully submerged. Only the roots should be in the water while the leaves remain above the surface to prevent rot and maintain water quality.

Why Pothos Are Popular for Aquarium Setups

Pothos are widely used in aquariums and aquaponic systems due to their hardiness, low light requirements, and ability to absorb nitrates. While not a true aquatic plant, its root system thrives in water and helps improve water quality by reducing ammonia and nitrate levels.

Benefits of Using Pothos Near or in a Fish Tank

Reduces harmful nitrates and ammonia in the water
Provides natural filtration without expensive equipment
Easy to grow and maintain for beginners
Enhances tank aesthetics with trailing vines
Supports beneficial bacterial growth on roots

How to Safely Use Pothos with Your Fish Tank

Proper setup is crucial to ensure both your fish and the pothos thrive. Follow these steps:

Step-by-Step Setup Guide

Cut a healthy pothos stem with at least 2–3 nodes.
Place the cutting in a container of dechlorinated water until roots develop (7–14 days).
Once roots are 2–3 inches long, position the plant so only roots enter the tank.
Use a hanging planter, lid cutout, or external filter compartment to keep foliage dry.
Ensure the tank receives low to moderate indirect light.

Common Mistakes to Avoid

Submerging leaves – leads to decay and poor water quality
Overcrowding roots – limits oxygen exchange and fish movement
Using soil-based potting mix inside the tank – causes cloudiness and algae
Exposing to direct sunlight – promotes algae overgrowth

Scientific Data: Pothos Nitrate Absorption in Aquariums

Study Duration (Weeks)	Tank Size (Gallons)	Initial Nitrate (ppm)	Final Nitrate (ppm)	Pothos Root Length (in)	Light Intensity (lux)
4	10	45	18	6	1500
6	20	52	12	9	1800
8	10	38	10	12	2000
6	5	60	25	5	1200

Table data source:1, 2

The data shows that pothos significantly reduces nitrate levels in aquariums over time, especially in tanks with moderate lighting and established root systems. Larger root mass and longer exposure correlate with greater nitrate removal efficiency.

Best Practices for Long-Term Success

To maintain a healthy balance between your pothos and aquarium ecosystem:

Trim roots monthly to prevent overgrowth
Wipe leaves regularly to remove dust and support photosynthesis
Avoid fertilizing near the tank—runoff can cause algae blooms
Monitor pH and hardness; pothos prefers slightly acidic to neutral water
Use activated carbon filters if you notice tannins or discoloration

Frequently Asked Questions About Pothos and Fish Tanks

Is pothos toxic to fish?

No, pothos roots in water do not release toxins harmful to fish. However, if fish ingest leaves, it may cause mild digestive upset due to calcium oxalate crystals. Keep foliage out of reach to be safe.

Can pothos survive fully underwater?

No, pothos cannot survive long-term when fully submerged. The leaves will yellow and rot within weeks. Only the roots should be in the water.

How fast do pothos grow in aquarium setups?

Under optimal conditions, pothos can grow 1–2 inches of new vine per week. Root growth is slower, averaging 0.5–1 inch per month in aquarium environments.

Do pothos help control algae in fish tanks?

Yes, indirectly. By absorbing excess nitrates and competing for nutrients, pothos limits resources available for algae, helping reduce outbreaks when combined with proper lighting and maintenance.

What fish are compatible with pothos setups?

Guppies, tetras, bettas, and corydoras are excellent choices. These species do not typically chew on roots and benefit from the improved water quality pothos provides.