Lotus Tonina

Tonina fluviatilis is a delicate stem plant from soft-water habitats in South America, and the lotus variant adds broader, slightly cupped leaves to the species' usual fine needle-like foliage. The effect is a two-tone stem where the lower portion carries narrow leaves and the upper part shifts to a wider, lighter form. Flowgrow covers the base species but not the lotus variant specifically; the published optimum temperature is 18 to 29 °C and pH 4 to 7, with high light and CO2 supplementation at 20–40 mg/l. Carbonate hardness must stay below 8 dKH — this is a plant for soft, acidic water, and in harder water the leaves curl and the stem stalls. Growth is medium, slower than most stem plants, which is partly why it is less common in the trade. It is placed in the midground, where its unusual leaf transition draws attention without dominating the layout. Propagation is by cutting the top half of a stem and replanting it, though the lower half does not branch as readily as rotalas — several cuttings may be needed to build a dense group. The difficulty on Flowgrow is very difficult for the base species, and the lotus variant is at least as demanding because the broader leaves are more prone to algae if CO2 or light fluctuates. Consistent soft water and stable CO2 are non-negotiable; this is not a plant for low-tech or hard-water setups.