AQUATICMOTIVShop

Hornwort (Ceratophyllum demersum)

Hornwort is less a plant you grow than a green engine you deploy: rootless, indestructible across a 35-degree temperature range, and so fast-growing it routinely out-eats algae in new setups. Ideal for coldwater tanks, ponds, fry cover, and cycling tanks. It also releases allelopathic compounds that actively suppress algae, and it is one of the few plants goldfish do not shred within days.

Care specifications

TypeStem
DifficultyEasy
LightLow (15–40 µmol PAR)
CO2Not needed
Fertilizer demandMedium
Growth rateFast
Max height40 in
Spread4 in
PlacementBackground, Floating
Attaches to hardscapeNo
Snail & shrimp safeYes
Temperature50–85 °F
pH6–8
ColorGreen
TrimmingFrequent
StylesJungle, Biotope

Get Hornwort

Hornwort

Hornwort (Ceratophyllum demersum)

$5.99 In stock

View product →

Propagation

Break a stem anywhere — every fragment keeps growing. There are no true roots; anchor it loosely or let it float.

Frequently asked questions

Why is my Hornwort dropping needles everywhere?

Needle drop is its trademark response to changed conditions — new water, new light, or being moved. The stems usually regrow cleanly once settled, but expect to clean the shed needles for a week or two after any change.

Can Hornwort be planted in substrate?

It has no roots, so 'planting' means anchoring the stem ends under a rock or in a weight — buried ends often rot. Most keepers either float it or pin it loosely and let the upper growth do its thing.

Go deeper

Find plants for your tank

Four questions — size, light, CO2, goals — and a ranked list matched to your exact setup.

Open the plant finder →