Pennywort Ultimate Guide: 6 Best Aquarium Uses

Picture this: tiny fish weaving through emerald-green leaves, their scales catching the light as they glide past clusters of coin-shaped foliage floating in crystalline water. A woman in Hunan province tried something most plant lovers never consider dropping pennywort, roots and all, straight into her indoor water garden. The results stopped people mid-scroll.

The internet erupted. Comments flooded in. This wasn’t just another plant hack; it was a full reimagining of how we grow aquatic plants indoor.

Pennywort, often called copper coin grass, isn’t just visually striking. Its round, polished leaves echo the shape of ancient Chinese currency, making it a symbol of prosperity and continuous wealth. The plant stays green through every season, never losing its charm to winter’s bite or summer’s heat a perfect addition for beautiful home gardens and inside plants displays.

What makes pennywort truly remarkable is its adaptability. It thrives in soil, in water, or a mix of both. Gardeners let it creep across outdoor beds, creating lush mats of green. Others tuck it into cute plant pot designs where it cascades like a living waterfall. Even a few stems in a small plants pot on your desk can bring a refreshing touch of nature into any workspace.

But growing it fully underwater? That opened an entirely new dimension for water plants indoor, turning ordinary plant care houseplant routines into a captivating experience for any indoor water garden enthusiast.

The guide below outlines the key steps needed to grow Dracaena with confidence.

Table of Contents

The Science Behind Submerged Pennywort

Pennywort isn’t pretending to be an aquatic plant. It actually is one. As an emergent species, it thrives in environments where many houseplants would simply drown. Its root system adapts to submerged conditions, drawing nutrients directly from water while its leaves perform photosynthesis beneath the surface or floating just above.​

In that Hunan aquarium, the pennywort didn’t just survive. It flourished. The leaves grew rounder, more vibrant, their green intensifying under aquarium lighting. Fish darted between stems, creating living paintings that shifted with every movement. The water itself stayed clearer; pennywort acts as a natural filter, absorbing excess nitrates that would otherwise cloud the tank and stress the fish.​

This isn’t magic. It’s biology working exactly as nature designed it.

Setting Up Pennywort in Your Aquarium

Getting started requires more than just dropping plants into water. The root system needs to stay intact. Pennywort without roots won’t develop new ones in time to survive. Even in ideal conditions, rootless cuttings fade within a day or two.​​

Before introducing pennywort to your tank, wash the roots thoroughly. Strip away any yellowing leaves or decaying root sections. Then comes the sterilization step: submerge the cleaned plant in either a fungicide solution or diluted potassium permanganate for roughly ten minutes. This prevents introducing harmful bacteria or parasites into your aquarium ecosystem.​

The roots need anchoring. In a bare-bottom tank, this becomes tricky. Some aquarium enthusiasts use volcanic rock, which provides weight and grip without harming delicate root structures. Another approach involves planting pennywort in a separate hydroponic container, using small stones to secure the base, then lowering the entire setup into the main tank once the plant establishes itself.​

The water parameters matter less than you might expect. Pennywort tolerates pH levels from 6.0 to 7.8, and temperature ranges between 68 and 82 degrees Fahrenheit rarely cause stress. It adapts to both soft and hard water, making it compatible with most freshwater fish species.​

The Half-Soil, Half-Water Method

Pure hydroponics works, but combining soil with water produces faster, healthier growth. The soil serves dual purposes: it anchors the root system firmly in place, and it provides a reservoir of nutrients that water alone cannot supply.​​

Meanwhile, the water layer above prevents the plant from drying out during periods of neglect. Life gets busy. Watering schedules slip. With a semi-aquatic setup, pennywort survives these lapses without showing stress.​

Start with a container that has no drainage holes. Layer pond mud, garden soil, or leaf mold across the bottom, filling about one-third of the container’s total height. Three to five centimeters of soil depth works well for most setups.​

Spread the pennywort roots evenly across this soil surface. Cover them with another thin layer of soil, pressing gently to eliminate air pockets. Add a layer of small pebbles on top; these keep the soil from clouding the water when you add it.​

Pour clean water slowly along the container’s edge, not directly onto the plant. The water level should sit two to three centimeters above the soil surface. This creates the semi-aquatic environment pennywort naturally prefers.

Light Requirements and Growth Patterns

Pennywort craves light with an intensity that surprises many first-time growers. Six to eight hours of bright, indirect sunlight each day keeps the leaves vibrant and the growth rate strong. Direct afternoon sun can scorch the foliage, but morning light or dappled shade throughout the day produces ideal conditions.​

For aquarium setups without access to natural sunlight, grow lights work perfectly well. Standard community tank lighting suffices for moderate growth, though higher-intensity setups produce noticeably faster expansion and denser leaf clusters.​

The plant grows toward its light source, a trait worth considering when positioning it in your tank. Place the light source above and slightly to one side, and the pennywort will angle itself accordingly, creating natural asymmetry that looks more organic than forced symmetry ever could.

Water Quality and Maintenance Cycles

Tap water often contains chlorine and other chemicals that stress aquatic plants. Let water sit exposed to air for one to two days before using it in your pennywort setup, allowing these chemicals to dissipate naturally. Rainwater works beautifully if you have access to clean collection systems.​​

Check the water level weekly. Top it off when it drops, but plan for a complete water change once each month. This prevents the buildup of organic waste that can turn water murky and foul-smelling.​

In aquarium environments with fish, pennywort actually improves water quality by absorbing excess nutrients. Nitrate levels drop as the plant feeds, creating a healthier ecosystem for aquatic life. Some aquarium keepers credit pennywort with resolving persistent algae problems, though it works through competition rather than direct suppression.

Fertilization Strategy for Maximum Growth

Every two weeks, add two to three drops of hydroponic nutrient solution directly into the water. Alternatively, bury three to five slow-release fertilizer pellets in the soil layer. Both methods provide the micronutrients pennywort needs for sustained growth.​​

Be cautious with fertilizer choices in aquariums containing shrimp or sensitive snail species. Some liquid fertilizers contain copper compounds that prove toxic to invertebrates even in small concentrations. Research your specific fertilizer’s composition before introducing it to a mixed-species tank.​

In soil-based setups, the substrate itself provides baseline nutrition. Rich pond mud or composted leaf mold contains organic matter that breaks down slowly, feeding the plant over extended periods. These setups typically require less supplemental fertilization than pure hydroponic systems.​

Pruning Techniques and Plant Management

Dense growth looks lush, but excessive leaf coverage blocks light penetration and reduces water circulation. Every few weeks, trim away yellowed leaves and thin out overcrowded sections. This promotes air flow and prevents the stagnant conditions that encourage fungal growth.​

Pennywort recovers quickly from aggressive pruning. If the plant becomes unruly or suffers damage, cut it back to just above the soil line. New shoots emerge within days, and full regrowth typically completes within a few weeks.​

In aquarium settings, regular pruning prevents pennywort from overwhelming the tank. The plant grows fast when conditions align with its preferences. Left unchecked, it can shade out other aquatic plants and limit swimming space for fish.

For a detailed pennywort care and aquarium planting guide, check out this Brazilian Pennywort care overview with tips on lighting, water parameters, and maintenance.

Creating Natural Wetland Conditions Indoors

The semi-aquatic growing method mirrors pennywort’s native habitat more closely than pure hydroponics or dry soil cultivation. In the wild, this plant colonizes marsh edges, shallow stream banks, and muddy shorelines where water levels fluctuate but moisture remains constant.​​

Replicating these conditions indoors produces the fastest growth rates and healthiest specimens. The soil provides stable nutrients and anchoring, while the standing water maintains humidity and eliminates the need for daily watering. It’s a low-maintenance approach that works with busy schedules rather than against them.​​

The aesthetic payoff matches the practical benefits. Watching pennywort grow in its element, with roots secure in rich soil and leaves spreading across water’s surface, brings a slice of wetland ecology into domestic space. It’s gardening that doesn’t require a garden.

Troubleshooting Common Growth Problems

Yellowing leaves typically signal nutrient deficiency or insufficient light. Increase fertilization frequency or move the plant to a brighter location. If yellowing appears suddenly after a water change, chlorine or chloramine in tap water might be the culprit. Switch to dechlorinated or aged water.​

Stunted growth often indicates poor water quality or root congestion. Test pH and temperature levels to confirm they fall within the optimal range. If the plant has been in the same container for several months, it may have exhausted available nutrients in the soil. Refresh the substrate or increase fertilization.​

Melting leaves can result from sudden environmental changes or incompatible fertilizers. Some liquid plant foods cause pennywort leaves to dissolve rather than nourish them. If melting occurs after introducing a new product, discontinue use immediately and perform a water change to dilute residual chemicals.

​With the right care and consistency, Dracaena can be grown effectively in any suitable space.

Products, Tools, and Resources

Successfully growing pennywort in aquatic environments requires a few key supplies that make the process smoother and more reliable.

For anchoring plants in aquariums, volcanic rock provides excellent grip without altering water chemistry. It comes in various sizes, allowing you to match the scale to your specific setup needs.

Hydroponic nutrient solution designed for aquatic plants delivers essential minerals without the harmful additives that stress fish and invertebrates. Look for products specifically labeled as aquarium-safe and copper-free if you keep shrimp.

Potassium permanganate solution serves dual purposes: it sterilizes plant roots before introduction to your tank and treats minor fungal infections without harming most fish species. Keep it on hand for all new plant additions.

Quality pond mud or organic potting soil without added fertilizers creates the ideal substrate for semi-aquatic setups. Avoid commercial potting mixes containing chemical additives, perlite, or vermiculite, which can cloud water and harm aquatic life.

A basic water testing kit measuring pH, ammonia, nitrite, and nitrate levels helps maintain optimal conditions for both plants and fish. Regular testing catches problems before they become visible.

Small decorative pebbles or river stones placed over soil prevent disturbance when adding water and create a finished aesthetic that looks intentional rather than improvised.

Aquarium grow lights with adjustable intensity settings give you control over pennywort growth rates and can compensate for rooms with limited natural sunlight.

Pruning scissors designed for aquascaping feature long, narrow blades that reach into tight spaces without disturbing surrounding plants or startling fish.

Slow-release fertilizer pellets formulated for aquatic plants provide months of nutrition from a single application, reducing maintenance frequency while supporting consistent growth.