Top 10 Types of Live Aquarium Plants That Require No CO2 Injection
Curated by Kory White · Fractional CRO, CRO SyndicateDirect Answer
The #1 pick for a no-CO2 aquarium plant is the Java Fern (Microsorum pteropus) — it thrives in low light, attaches to driftwood or rock, and requires zero fertilization to stay healthy. The runner-up is Anubias barteri var. Nana**, a bulletproof rhizome plant that survives neglect and low-tech setups.
Both are ideal for beginners and busy aquarists who want a lush planted tank without investing in CO2 injection systems, pressurized cylinders, or daily dosing routines.
How We Ranked These
We evaluated each plant against five criteria relevant to a no-CO2 (low-tech) aquarium environment:
- Light Tolerance — Can it survive under standard LED strips (0.5–1.5 watts per gallon) or low-output T5/T8 bulbs? Plants requiring >2 WPG or high PAR were excluded.
- Growth Rate & Maintenance — Slow-to-moderate growers that don’t demand frequent trimming or heavy nutrient dosing scored higher. Fast growers that outcompete algae without CO2 were also considered.
- Nutrient Flexibility — Plants that thrive on fish waste alone or with minimal root tabs (e.g., API Root Tabs, Seachem Flourish Tabs) ranked above those needing liquid fertilizers.
- Algae Resistance — Species naturally resistant to algae (due to tough leaves or slow growth) earned bonus points, as algae is the primary challenge in low-tech tanks.
- Availability & Cost — Widely available from major retailers (Buce Plant, Aquarium Co-Op, Petco) and priced under $10 per pot or bunch were prioritized. All prices are as of early 2027.
1. Java Fern (Microsorum pterosum) 🏆 BEST OVERALL
Java Fern is the undisputed king of low-tech planted tanks. This rhizome plant (never bury the rhizome in substrate) attaches to wood or rock using thread or super glue gel (e.g., Seachem Flourish Glue). It grows at a slow-to-moderate rate under any light from 0.5–2 WPG, and it absorbs nutrients directly from the water column — no root tabs needed.
A single pot costs $5–$8 at Buce Plant or Aquarium Co-Op.
Use it as a background plant along driftwood or as a midground accent. Its tough, leathery leaves resist algae and herbivorous fish like Siamese algae eaters and otos. The only maintenance is removing old leaves that turn brown — cut them at the base.
Java Fern propagates via plantlets that form on leaf tips; you can snip them off and glue them to new surfaces. It’s also one of the few plants that can survive in brackish water (specific gravity up to 1.005), making it a versatile choice for mollies or gobies.
2. Anubias barteri var. Nana 💎 BEST VALUE
Anubias nana is the most cost-effective no-CO2 plant you can buy. A single rhizome with 3–5 leaves costs $6–$9 and will last years. It’s a slow grower that needs virtually zero trimming — perfect for nanotanks (5–10 gallons) or as a foreground plant in larger setups.
Like Java Fern, it must be attached to hardscape; burying the rhizome causes rot.
Anubias nana thrives under low light (0.5–1 WPG) and can even survive in shaded corners of the tank. It’s highly resistant to algae because of its thick, waxy leaves — even black beard algae struggles to attach. For a pop of color, try Anubias nana ‘Petite’ (leaves 1–2 cm) or Anubias coffeefolia (larger, crinkled leaves).
Use Seachem Flourish Excel as a liquid carbon source (not CO2) to boost growth slightly, but it’s optional. A 2-ounce bottle of Excel costs $12 and lasts 3–4 months in a 20-gallon tank.
3. Java Moss (Taxiphyllum barbieri)
Java Moss is the most forgiving moss in the hobby. It grows as a floating mat or attaches to mesh, wood, or rock with fishing line. It requires no CO2 and low light (0.5 WPG minimum).
A golf-ball-sized portion costs $5–$7 and will cover a 12x12-inch area in 3–4 months. Use it as a spawning medium for shrimp (cherry, Amano) or as a foreground carpet when tied to stainless steel mesh (e.g., ADA Moss Mesh).
Java Moss is indestructible — it can survive total darkness for weeks (useful during blackouts to kill algae) and regrows from even a single strand. The downside: it collects debris and can trap mulm, so use a turkey baster to blast it clean during water changes. For a neater look, try Weeping Moss (Vesicularia ferriei) — it grows downward like a curtain — but Java Moss remains the best value for low-tech tanks.
4. Cryptocoryne wendtii
Cryptocoryne wendtii is the go-to rosette plant for no-CO2 setups. It forms a compact cluster of leaves (green, bronze, or red) that grows 4–8 inches tall. It’s a root feeder, so use root tabs (e.g., API Root Tabs — $8 for 10 tabs) pushed into the substrate near the crown.
Light requirements are low to moderate (1–1.5 WPG). A potted plant costs $6–$9 at Petco or Aquarium Co-Op.
The key trait: Crypt melt. When first planted or after a water change, leaves may dissolve into mush — this is normal. The plant will regrow from the root system in 2–4 weeks.
Don’t remove the crown during melt. Once established, it’s bulletproof and will send out runners to form a dense foreground. Pair with Java Fern in the background for a classic low-tech scape.
Avoid moving it after planting — Crypts hate root disturbance.
5. Hornwort (Ceratophyllum demersum)
Hornwort is the fastest-growing no-CO2 plant — it can add 1–2 inches per day under moderate light (1.5 WPG). It’s a floating stem plant that absorbs nutrients from the water column, making it an excellent nitrate sponge. A bunch of 5–6 stems costs $4–$6 at Buce Plant or Aqua Forest Aquarium.
It’s also cold-water tolerant (down to 50°F), ideal for unheated tanks or goldfish setups.
The catch: Hornwort sheds needle-like leaves when stressed (e.g., sudden temperature change). This creates debris that can clog filters — use a pre-filter sponge on your intake. It also requires consistent light; too little causes the lower stems to go bare.
To propagate, simply cut the stem and let the top float. For a more stable option, try Water Wisteria (Hygrophila difformis) — it grows slightly slower but doesn’t shed as much.
6. Amazon Sword (Echinodorus bleheri)
Amazon Sword is a classic background plant that reaches 12–20 inches tall. It’s a heavy root feeder — you must use root tabs (e.g., Seachem Flourish Tabs — $12 for 10 tabs) buried 1–2 inches deep. Light requirement is moderate (1.5–2 WPG); low light causes leggy growth.
A single plant costs $5–$8 at PetSmart or Buce Plant.
It’s not ideal for nano tanks (needs at least 20 gallons). The leaves are tough and can withstand goldfish and cichlids that uproot other plants. Amazon Sword propagates via runners that produce baby plants — snip them off and replant.
One downside: it produces emersed leaves (with stems) that may melt when submerged — just trim them. For a smaller alternative, try Echinodorus parviflorus (4–6 inches tall).
7. Marimo Moss Ball (Aegagropila linnaei)
Marimo Moss Balls are actually algae, not moss, but they’re a zero-maintenance addition to any no-CO2 tank. They grow 1 cm per year under low light (0.5–1 WPG) and don’t need trimming. A single ball costs $4–$6 at Petco or Aquarium Co-Op. They absorb nitrates and provide grazing surface for shrimp.
The trick: rotate them every water change to keep them round — they’ll flatten on one side if left still. They can also be unraveled to form a carpet (though this is slow). Avoid direct sunlight (causes browning).
Marimo is cold-water tolerant (down to 60°F) and safe with all fish. For a larger accent, buy a Marimo colony (3–5 balls) for $15–$20.
8. Vallisneria spiralis (Italian Val)
Vallisneria is a grass-like background plant that grows 12–24 inches tall. It’s a runner plant that spreads rapidly under moderate light (1.5 WPG). A bunch of 5–6 plants costs $6–$8 at Buce Plant or Aqua Lab Aquaria.
It does not need CO2 but benefits from iron-rich root tabs (e.g., Seachem Flourish Iron — $10 for 100 mL).
The challenge: Vallisneria is sensitive to liquid carbon (Excel) — it can melt leaves. Avoid dosing Excel if you have Val. It also prefers hard water (GH > 8 dGH); soft water causes stunted growth.
Use it to create a jungle-like background that fish like guppies and platies love to hide in. Trim runners to control spread — they can take over a 20-gallon tank in 3 months.
9. Cryptocoryne parva
Cryptocoryne parva is the smallest Crypt (2–4 inches tall) and the only one that works as a true foreground carpet in low-tech tanks. It’s a slow grower that needs moderate light (1.5–2 WPG) and root tabs (e.g., API Root Tabs). A pot of 5–7 plants costs $8–$10 at Buce Plant or Aquarium Co-Op.
It’s not for beginners — it’s prone to Crypt melt and can take 6 months to form a dense carpet. But once established, it’s low-maintenance and won’t outgrow the tank. Use it in shrimp tanks or nanotanks (5–10 gallons).
For a faster carpet, use Dwarf Sagittaria (Sagittaria subulata) — it grows 4–6 inches tall and spreads via runners under low light.
10. Water Sprite (Ceratopteris thalictroides)
Water Sprite is a floating or rooted fern that grows 1–2 inches per week under moderate light (1.5 WPG). It’s a nitrate sponge that can be left floating (provides shade for fish) or planted in substrate. A bunch of 3–4 stems costs $5–$7 at Aquarium Co-Op or Buce Plant.
It’s cold-water tolerant (down to 60°F) and safe with goldfish.
The downside: it sheds leaves when moved or stressed, creating debris. It also blocks light if left floating — limit to 25% of the surface area. Propagate by cutting the stem and letting the top float. For a more stable floating option, try Duckweed (Lemna minor) — but beware: it’s invasive and hard to remove once introduced.
FAQ
? Can I use liquid carbon (Seachem Flourish Excel) instead of CO2? Yes — Excel provides a carbon source that boosts growth in low-tech tanks. Dose 1 mL per 10 gallons daily. But avoid it with Vallisneria and Hornwort, which can melt.
? How often should I fertilize no-CO2 plants? Most low-tech plants need root tabs every 2–3 months (e.g., API Root Tabs) and liquid fertilizer weekly (e.g., Seachem Flourish — $15 for 250 mL). Over-fertilizing causes algae.
? What light is best for no-CO2 plants? A NICREW Classic LED (18–24 inches, $30–$40) or Hygger 24/7 LED ($50–$60) with 0.5–1.5 WPG is ideal. Avoid strong lights (>2 WPG) without CO2 — it triggers algae.
? Can I grow carpet plants without CO2? Yes — Cryptocoryne parva (slow) or Dwarf Sagittaria (faster) can carpet under moderate light with root tabs. Avoid Monte Carlo or Dwarf Baby Tears — they need CO2.
? How do I prevent algae in a low-tech tank? Use floating plants (Hornwort, Water Sprite) to reduce light, manual removal with a Mag-Float glass cleaner ($15), and Siamese algae eaters (1 per 20 gallons). Avoid overfeeding.
? What’s the hardiest no-CO2 plant for goldfish? Java Fern and Anubias nana — goldfish won’t eat the tough leaves. Hornwort works but may be uprooted. Avoid Crypts — goldfish dig them up.
? Can I use soil substrate instead of root tabs? Yes — Fluval Plant & Shrimp Stratum ($20 for 8.8 lbs) or ADA Amazonia ($35 for 9 lbs) provide nutrients for 6–12 months. But they leach ammonia initially — cycle the tank first.
Sources
- Java Fern care guide at Buce Plant
- Anubias nana care at Aquarium Co-Op
- Low-tech plant list at The Spruce Pets
- Seachem Flourish Excel dosing instructions
- NICREW Classic LED light specs
- Cryptocoryne wendtii care at Tropica
- Hornwort care at Aqua Forest Aquarium
- Marimo Moss Ball care at Petco
Bottom Line
For a no-CO2 planted tank, choose Java Fern for reliability, Anubias nana for value, and Hornwort for rapid nitrate control. All ten plants thrive under standard LED lights, need only fish waste or occasional root tabs, and resist algae when properly maintained. Start with a 20-gallon tank and a NICREW Classic LED — you’ll have a lush, low-maintenance aquascape in 3–4 months.
*Top 10 types of live aquarium plants that require no CO2 injection for low-tech planted tanks in 2027.*