Syngonanthus inundatus Care Guide
Syngonanthus inundatus is a fine-leaved Brazilian pipewort stem plant for blackwater scapes, demanding very soft acidic water, strong light and CO2.
Compiled by Aquairi from published sources · Published · Updated
Overview
Syngonanthus inundatus (often sold as Syngonanthus cf. inundatus) is a fine stem plant of the pipewort family with needle-like foliage typical of the family. It is a demanding midground plant for soft-water, high-tech setups. The form was originally marketed as Tonina sp. 'Manaus' before being placed in Syngonanthus.
Taxonomy
- Family: Eriocaulaceae
- Genus: Syngonanthus
- Scientific name: Syngonanthus inundatus
- Former trade name: Tonina sp. 'Manaus'
Habitat
Native to Brazil and the broader soft, blackwater rivers of Central and South America. These environments are acidic and low in dissolved minerals.
Tank requirements
- Temperature: 22-28 °C (72-82 °F)
- pH: 5.0-6.5 (acidic preferred)
- GH: 0-4 °dGH
- KH: 0-2 °dKH (low alkalinity)
- Lighting: high
- CO2: required (~20-40 mg/L)
- Placement: midground
- Height: up to ~25 cm
Cultivation
Strict soft-water conditions are essential, with carbonate hardness ideally below 2 dKH and acidic pH below 7. The plant should not be shaded and needs strong light plus CO2. A nutrient-rich acidic soil substrate, with peat in the lower layer and at least 10 cm depth, is a significant advantage. Growth is medium and the species can also grow emersed.
Propagation
Propagated from cuttings: side shoots or trimmed stem tops are replanted to root in the substrate.
Propagating Syngonanthus inundatus
Overview
Syngonanthus is a genus in the family Eriocaulaceae, native to tropical regions of Latin America. Aquarium forms come from the Amazon, where they grow in very soft blackwater rivers. Syngonanthus inundatus is one of the finer, more delicate members, with needle-like leaves on a slow-growing rosette-stem, and it demands stable soft water and strong light.
Propagation Method
Like its Eriocaulaceae relatives, Syngonanthus is propagated vegetatively rather than by buying new stock. Some Syngonanthus species develop side shoots as they grow, and a large specimen can also be split into halves at the base. Both the detached side shoots and the divided crowns are replanted as new plants.
Step-by-Step
- Grow a parent plant strongly so it develops side shoots or a dense multi-headed crown.
- For side shoots: gently detach a shoot once it carries its own ring of leaves.
- For division: lift the plant and split the crown into two halves, each with roots and leaves.
- Trim away damaged roots and replant each piece into acidic aquasoil.
- Provide good light and CO2 at substrate level so the divisions settle and resume growth.
Conditions for Healthy Growth
- Soft water, less than 2 dKH.
- Acidic, nutrient-rich aquasoil substrate.
- Good lighting with no shading — it must not be overgrown by neighbours.
- CO2 injection present, though it need not be very high.
- Stable parameters, mimicking soft Amazon blackwater.
Trimming & Maintenance
Because growth is slow, trim sparingly and mainly to remove old or shaded leaves. Keep faster neighbours cut back so light reaches the crown, and use this routine pruning as a chance to harvest side shoots for propagation.
Common Challenges
Being delicate, Syngonanthus inundatus reacts badly to hard water and rising carbonate hardness. Shading, weak CO2 at the substrate, or unstable parameters slow it further and reduce side-shoot output, so there is little to divide. Maintaining a stable, acidic soft-water environment is the key to a propagatable plant.