Water wisteria
A fast-growing stem plant whose leaf shape changes dramatically with light — finely divided in strong light, broad and simple in weak.
Requirements
- Scientific name
- Hygrophila difformis
- Family
- Acanthaceae
- Light
- Medium
- CO₂
- Not required
- Nutrients
- moderate
- Growth rate
- Very fast
- Placement
- Background
- Feeding
- both
- Temperature
- 22–28 °C
- pH
- 6–7.8
- Hardness
- 2–18 °dGH
- Height
- 25–50 cm
Identity
- Common name
- Water wisteria
- Scientific name
- Hygrophila difformis
- Family
- Acanthaceae
How to plant it
The commonest way to kill an aquarium plant is to install it wrongly. This is the first thing to get right.
Roots buried, crown above the substrate
Nutrition reaches this plant mainly through both roots and leaves, so either route works.
Growing conditions
| Input | Requirement | Notes |
|---|---|---|
| Light | Medium | Match plants to the light you have rather than raising light to suit the plant — that grows algae. |
| CO₂ | Not required | Not a requirement, though growth is faster with it. |
| Nutrients | moderate | Dose a complete liquid fertiliser. |
| Temperature | 22–28 °C | |
| pH | 6–7.8 | |
| Hardness | 2–18 °dGH | |
| Growth rate | Very fast |
Propagation
Cuttings; also grows from a floating stem.
Emersed growth and melting
Commercially grown out of water. Expect the emersed leaves to die back after planting while new submersed-form leaves grow from the crown. This is a conversion, not a disease.
Common problems
- leaf shape changes
- outgrows tank
- melts after transplant
Work from the observation: melting, yellow leaves, holes in leaves and poor growth.
Fish and invertebrate compatibility
- Resists grazing
- poor
- Resists digging
- poor
Worth knowing
- The change in leaf shape alarms people. It is a normal light response, not a deficiency.
Evidence
| Claim | Value | Evidence type | Confidence | Source |
|---|---|---|---|---|
| scientific name | Hygrophila difformis | Observed / measured | high confidence | Plants of the World Online |
| temperature | 22–28 °C | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| light requirement | medium | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| co2 requirement | not-required | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| growth rate | very-fast | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| placement | background | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| ph | 6–7.8 pH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| general hardness | 2–18 °dGH | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
| height | 25–50 cm | Aquarium-literature consensus | moderate confidence | AquariumHQ husbandry synthesis |
Why we say this
What each figure on this page rests on, and how far that is from being independently established.
Every figure on this page has a provenance. Open any claim to see what AquariumHQ holds for it, which sources say what, and what a claim of that kind actually needs. Different claims need different evidence: an accepted scientific name is settled by one authority, while a legal restriction needs a current primary instrument. A single source is often the right answer rather than a thin one. Light and CO2 categories are aquarium conventions rather than measurements, and are labelled as such — AquariumHQ has taken no PAR readings and does not publish figures it has not taken.
scientific nameAquariumHQ's own position, externally checkableLimited evidence — treat with caution.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: accepted botanical name — 1 authoritative source in an appropriate context. This class needs 1 independent origin of at least primary-compilation authority, and 0 are held.
What would improve this: Go and read a source. This is reachable and has not been reached.
temperatureAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
light requirementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Keep the rationale current. There is no source to find.
co2 requirementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Keep the rationale current. There is no source to find.
growth rateAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Keep the rationale current. There is no source to find.
placementAquariumHQ's judgement — no authority publishes thisAquariumHQ's own position, derived from evidenced inputs.
No external authority publishes this. The rationale carries the reasoning.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Keep the rationale current. There is no source to find.
phAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
general hardnessAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: how to grow the plant — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.
heightAquariumHQ's own position, externally checkableAquariumHQ's own position, derived from evidenced inputs.
AquariumHQ's own position on a claim an external source could support.
What this kind of claim needs: size a well-kept specimen reaches — no external source is required, provided AquariumHQ shows its reasoning. No external source is required for this class. AquariumHQ's position stands on its stated reasoning.
What would improve this: Go and read a source. This is reachable and has not been reached.