Aquaponics for Beginners – Grow Plants on Top of a Fish Tank for Lush Houseplants, Herbs, and Salads

Aquaponics combines hydroponics (growing plants in water) with aquaculture (raising fish) in a closed-loop system. It sounds like a project that requires a greenhouse, a biology degree, or at least a lot of money. It doesn’t. A houseplant dangling its roots into a fish tank is all it really takes to get started – though you can just as easily grow edibles like leafy greens and herbs.

When I first discovered aquaponics, it opened up a whole new way of growing. I was struck by how something so simple could be so effective – bringing plants and aquatic life together in a self-sustaining system, where waste from fish or shrimp feeds the plants, and the plants help clean and filter the water.

Early on, I worked on larger projects – both manmade setups and natural pond ecosystems, along with a couple of serious planted tanks. What I took from all of them is that the fundamentals don’t change with scale. A 5-gallon tank and a 500-gallon system both work the same way: plants filter waste, creatures process what plants can’t, and the right balance means less work for you.

Since becoming disabled and moving into a wheelchair, the way I approach growing things has changed completely. The elaborate setups I used to build aren’t realistic anymore. What works for me now is a cluster of peace lilies with their roots hanging into my axolotl’s tank, a handful of cherry shrimp, and a few snail species working a mixed rock and sand substrate – a system that mostly takes care of itself while I watch it from my chair.

However simple or complex you make it, the system itself doesn’t change.

What Is Aquaponics, and Why Does It Work?

Aquaponics is the term for what happens when fish waste feeds plants and plants filter water. Fish produce ammonia through waste and respiration, which beneficial bacteria in the substrate and biofilm convert first to nitrite, then to nitrate. Plant roots absorb those nitrates as fertilizer, helping them grow while keeping the water cleaner.

In a balanced system, that cycle does most of the work for you. There’s little need for mechanical filtration or added fertilizer, and maintenance is largely limited to occasional parameter checks. Even a partial setup – a few plants, a few fish, some shrimp – can noticeably reduce how often manual water changes are needed.

A fully self-sustaining ecosystem builds on this by adding a layered cleanup crew: shrimp, snails, microorganisms, and bottom-dwellers that each process waste at different levels of the tank.

Because the system recirculates water and reuses waste as nutrients, aquaponics can be more resource-efficient than traditional growing methods.

Types of Aquaponics Systems

Most home aquaponics setups fall into one of a few basic types:

• Media bed systems – plants grow in a solid substrate like gravel or clay pellets
• Raft (deep water culture) – plants sit on floating rafts with roots submerged
• Nutrient film technique (NFT) – a thin stream of water flows past plant roots
• Vertical or tower systems – stacked growing spaces for small footprints

The setup in this guide is closest to a simple media-based system, scaled down for a home tank.

Shop Aquaponic Kits

My Simple, Low-Maintenance Setup

My current setup sits somewhere between those two approaches – not fully closed, but far more self-managing than a standard tank. The axolotl produces waste, the shrimp and plants deal with much of it, and the peace lilies visibly grow off what would otherwise accumulate in the water.

The root structure also provides shelter and foraging space for shrimp, keeping them more active and healthier. Everything is feeding something else.

The tank itself is taller than it is wide. That isn’t a requirement, but it works well – the extra depth gives the roots more room to trail and the shrimp more vertical space to use. A standard wide tank does the job just as well.

I’m currently running nothing more than the standard tank light, raised slightly to clear the plants. It’s still a work in progress, and I like it that way. The challenge of building something useful from whatever is at hand is half the point.

What I use right now is genuinely minimal: 316L stainless-steel wire bent to hold plant stems at the tank rim (aquarium-safe, bendable, and inexpensive), a recycled floating ring from a mini fogger repurposed to support roots at the surface, and the stock light raised on risers.

That’s it. You can replicate this setup for nearly nothing, or build something considerably more advanced. Either way, it works.

The Establishing Period: What to Expect First

Before any aquaponic setup runs itself, it has to cycle – and that period takes patience and some hands-on attention. Cycling is the process of building up the beneficial bacterial colonies that convert fish waste from toxic ammonia into relatively harmless nitrate.

In a new tank, ammonia and nitrite will spike before those bacteria are established. During this phase, water changes are needed more frequently, sometimes every few days, to keep levels safe for any fish or shrimp already in the tank. This is normal and expected. It doesn’t last forever.

For beginners, API test strips are the most practical starting point – they test pH, ammonia, nitrite, and nitrate in one dip and are easy to read without any mixing or counting drops. They’re not as precise as the liquid test kit, but they’re more than accurate enough to catch a spike before it becomes a problem.

Once the tank is established and parameters are stable, stepping up to the API Freshwater Master Test Kit gives more reliable readings for long-term monitoring.

The cycle typically takes three to six weeks, depending on tank size, stocking level, and how much surface area is available for bacteria to colonize. Adding a handful of substrate or filter media from an already-cycled tank speeds this up considerably.

Common Mistakes to Avoid

• Adding too many fish too quickly – this overwhelms the system before bacteria are established
• Underplanting – not enough plant mass means less filtration
• Overfeeding – excess food quickly turns into waste spikes
• Skipping water testing early on – problems build before they’re visible

Most issues come down to imbalance – too much input, not enough biological capacity to handle it.

Starting Small: The Minimal Setup

The simplest possible aquaponic setup is an existing tank with a plant clipped to the rim and roots trailing into the water. That’s genuinely all it takes to start. A pothos, philodendron, or peace lily will begin pulling nutrients from the water within days, and the improvement in water quality is often noticeable within weeks.

This kind of setup is ideal for beginners, small spaces, or anyone looking for a low-maintenance system. No additional equipment is required beyond what most tanks already have.

Can a Tank Run Without a Pump or Air Stone?

Yes – with the right setup and stocking level. Still water can support a low-tech aquaponic system if plant coverage is high and the bioload is light.

Surface agitation from plants breaking the water line, along with natural gas exchange at the surface, provides enough oxygenation for small, low-demand fish (like a single betta), shrimp, and snails. This is essentially a Walstad or natural planted tank approach – heavily planted, lightly stocked, and relying on biology rather than mechanical equipment to maintain balance.

The trade-off is that these setups are less forgiving. Any spike in waste that outpaces the plant and bacterial capacity has nowhere to go. A tank without a pump has less margin for error and requires closer observation during the establishing period.

It works, but it rewards patience and a light hand with feeding.

What the Minimal Setup Needs

• Tetra AquaSafe Plus water conditioner – treat any tap water before it goes in. This is what I use. Seachem Prime is a strong alternative – more concentrated and able to temporarily detoxify ammonia during cycling.
• API test strips – enough to monitor the cycle and catch problems early. You can graduate to a liquid test kit once the tank is stable.
• Hygger digital thermometer or the Zacro 2-pack – temperature swings are easy to miss in open-top tanks. These take seconds to stick on and give a constant read. Useful, but not essential.
• 316L stainless steel wire – bend a simple holder to support plant stems at the rim. Aquarium-safe, inexpensive, and effectively permanent.
• Floating plant holder – for surface plants like peace lilies and pothos, Plus Floating Aquarium Plant Holders keep roots suspended neatly in the water. Clean, purpose-built, and well-sized for smaller setups.
• Clip-on net pots – these 1.57-inch transparent aquarium cultivation pots attach to the glass with suction cups, holding plants in place while roots grow into the water. Ideal for mid-water placement or tanks where surface floating isn’t practical.

Lighting for the Beginner Setup

The stock light that came with the tank is enough to get started, especially for shade-tolerant plants like peace lilies and pothos. Raise it on small risers or prop it slightly above the tank edge to give the plants growing at the surface enough headroom.

As the system establishes and plant coverage fills in, the plants themselves help diffuse and moderate the light reaching the water. That’s usually the point where upgrading to a more capable light starts to make a noticeable difference in plant growth.

The light I prefer for a setup like this, once it’s established, is the Spider Farmer SF1000D – full spectrum, dimmable, runs cool, and built with Samsung diodes that hold up over time. In a planted tank, the canopy helps moderate its intensity so the water isn’t exposed to the full output directly.

The Mars Hydro TS 600 is a solid alternative if you’re working with a smaller budget.

Whichever route you take, look for a true full-spectrum light – white output across the photosynthetic range, rather than just red and blue diodes.

Plants That Work in a Small Setup

Peace lilies are an easy entry point, but the range of plants that thrive with their roots in tank water is broader than most people expect. The rule of thumb is simple: the more plant mass in contact with the water, the better the filtration. More roots mean more surface area for beneficial bacteria and greater nitrate uptake.

Surface Plants (Roots in Water, Leaves Above)

• Peace lily (Spathiphyllum) – forgiving, root-happy, and tolerant of low light. The ideal starting point.
• Pothos (Epipremnum aureum) – extremely vigorous, roots quickly in water, and excellent at removing nitrates.
• Philodendron – similar to pothos in behaviour, with roots that trail easily from a rim holder or clip.
• Lucky bamboo (Dracaena sanderiana) – can grow with stems partially submerged and handles a wide range of conditions.
• Spider plant (Chlorophytum comosum) – surprisingly effective and easy to propagate from runners.
• Mint, basil, and soft herbs – fast-growing, thrive on the available nutrients, and produce something edible. Microgreens also work in a small floating tray. Just make sure only the roots are in the water.
• Water lettuce and duckweed – float on the surface, grow quickly, and act as excellent nitrate sponges. Keep duckweed contained, or it will take over.

While leafy greens and herbs are the easiest starting point, a well-balanced system can also support fruiting plants like tomatoes, cucumbers, and even strawberries.

Submerged Aquatic Plants

• Java moss (Taxiphyllum barbieri) – attaches to rocks and driftwood, thrives in low light, and provides excellent shrimp habitat.
• Java fern (Microsorum pteropus) – attach to hardscape rather than planting in substrate. Nearly indestructible, and currently what I use in my own tank – though it can spread quickly if left unchecked.
• Anubias – attach the rhizome to rock or wood. Extremely tolerant of low light and fluctuating conditions.
• Hornwort (Ceratophyllum demersum) – can float or anchor loosely, fast-growing and highly effective at nitrate removal.
• Water wisteria (Hygrophila difformis) – a fast-growing mid- to background plant that does well under moderate light.
• Vallisneria – grass-like and spreads via runners. Better suited to larger or more stable setups.

Substrate and the Cleanup Crew

The substrate is the engine of the biological system. It provides surface area for beneficial bacteria, determines which cleanup species can thrive, and influences how waste moves through the tank.

My current setup uses a mixed rock and sand substrate – coarser material layered with fine sand in different zones. This gives trumpet snails space to burrow and process debris, while shrimp forage across both surfaces. A mixed substrate is the most flexible approach, but any substrate can work if it’s matched to the livestock.

Fine Sand

Best for cherry shrimp, pygmy corydoras, Malaysian trumpet snails, and nerites. Waste stays on the surface, making it easy to see and graze.

• Cherry shrimp (Neocaridina) – the go-to cleanup crew for small tanks. They graze constantly on biofilm and algae and breed readily in stable conditions.
• Nerite snails – don’t breed in freshwater and provide excellent algae control on glass and hardscape.
• Malaysian trumpet snails – burrow through fine substrate, preventing compaction and anaerobic pockets. They reproduce quickly but are highly effective.
• Pygmy corydoras – gentle bottom-dwellers that sift sand without disturbing plant roots.

Gravel, Rock, or Mixed

Best for Amano shrimp, mystery snails, blackworms, and freshwater clams in more advanced setups.

• Blackworms (Lumbriculus variegatus) – live within substrate gaps, process organic waste directly, and can double as a live food source.
• Freshwater clams (Corbicula fluminea) – filter-feeders that remove suspended particles from the water column. Require fine organic matter or phytoplankton, but can significantly improve water clarity.
• Amano shrimp – larger than cherry shrimp and better suited to coarser substrates and heavier algae loads.
• Mystery and pond snails – handle tougher debris and higher waste levels than nerites.

Bare Bottom

Best for axolotls and fish prone to swallowing gravel. Waste is easy to see and siphon, but there is less surface area for beneficial bacteria.

• Sponge filter – essential in bare-bottom setups, providing both mechanical filtration and a surface for bacterial colonisation.

Scaling Up: More Complex Setups

Everything above works in a small tank with minimal equipment. Scaling up is mostly a matter of adding what a larger system needs: more water movement, greater plant capacity, a more robust cleanup crew, and stronger lighting.

The principles don’t change – the margin for error just gets wider.

Additional Equipment for Larger Setups

• Hygger quiet aquarium air pump with an air stone – improves oxygen exchange in larger or more heavily stocked systems. Models with multiple outlets can run several tanks from one unit.
• Aquarium sponge filter – provides mechanical filtration and additional surface area for beneficial bacteria. Particularly useful during cycling or in heavily stocked tanks.
• 2-inch net cups (50-pack) – use with floating planter baskets and a growing medium like hydroton for plants that need more root support.
• Larger floating planters – Treela floating planter baskets are designed for pond or larger tank use, with drainage holes and enough capacity to support significantly more plant mass than smaller holders.
• Grow tray or suspended shelf – a hydroponic net cup tray suspended over the water with roots hanging through expands plant capacity without modifying the tank.
• Water pump for circulation – a small submersible water pump moves water from the tank to an elevated grow bed and back again. Standard for flood-and-drain or continuous flow systems.
• Grow light – for larger or multi-tank setups, upgrade to the Spider Farmer SF2000 – this covers a 2’ x 4’ (60 x 120 cm) area and supports both leafy and fruiting plants effectively.

Long-Term Maintenance

Once the system is established and parameters are stable, the day-to-day maintenance load drops considerably. Ammonia and nitrite should sit at or near zero, while nitrates will still accumulate gradually. The plants help, but a partial water change every two to three weeks remains good practice in most setups.

Always add a water conditioner to any tap water before it goes into the tank. Check temperature and run a quick parameter test monthly, and top off evaporated water as needed – especially in open-top systems. Beyond that, there’s very little to do once things are running smoothly.

The larger the system, the more stable it tends to be. Greater water volume provides more buffering capacity – a spike that could crash a 5-gallon tank barely registers in 50 gallons. A more diverse mix of species also adds redundancy to the cleanup chain.

Even a minimal setup – peace lilies, an axolotl, shrimp, and a stock light – can run well with very little input. It takes patience to get there, and some hands-on management during the establishing period, but the payoff is a system that largely runs itself.

Something green growing out of the top of a fish tank, with almost no effort required, is a good deal, however you build it.