Eleocharis sp. "Mini"

Geographic Origin and Habitat: There is no true wild geographic distribution for Eleocharis sp. "Mini". Although native species of the *Eleocharis* genus (such as *E. parvula* and *E. acicularis*) hail from coastal marshes and muddy banks of rivers and lakes worldwide, the "Mini" variant is a very rare and sought-after mutation (cultivar) isolated by the famous aquarist Tom Barr and subsequently propagated in vitro by laboratories like Tropica. Therefore, its native "habitat" is the modern planted aquarium.

Taxonomy and Genetics: It belongs to the Cyperaceae family (the sedges). The genus name derives from the Greek *elos* (marsh) and *charis* (grace). It is often confused with *Eleocharis parvula*, but differs genetically due to the total and irreversible suppression of the leaf elongation gene: even under poor light or deep water, the "Mini" variant flatly refuses to exceed 3-5 cm in height.

Physical Structure: The architecture is extremely simple: it is composed of a dense subterranean (hypogeal) network of thin, creeping white rhizomes (runners). From these stoloniferous nodes, tiny tufts of thread-like leaves (needles or culms) sprout upwards without a central stem, and very fine capillary roots grow downwards. Vegetative reproduction occurs via the explosive lateral branching of runners under the sand.

Color and Texture: Chromatically, it offers a spectacular, intense, and bright lawn green (apple green or spring green), which never turns yellow if well-nourished. The texture of the needles is silky, soft, and extremely flexible under the push of the current, bending harmoniously and sinuously. They create a dense carpet that visually resembles the softness of velvet or miniature golf courses.

Lighting and CO2: Although its genetic height is locked, its density and health depend entirely on light and carbon. To form a compact, suffocating lawn in a few weeks, it requires medium-high lighting (PAR > 60). Under weak light, the needles will remain sparse and thin. Pressurized CO2 injection (20-30 mg/l) is not strictly mandatory for its survival, but is absolutely essential to achieve the legendary and thick "lawn effect" in the Iwagumi style.

Nutrition and Substrate: It is an exclusively benthic plant: it absorbs all of its macronutrients (nitrogen, phosphorus, and iron) through its extensive root network in the substrate. It obligatorily requires a fertile bottom, preferably an allophane substrate (aquasoil) or enriched potting soil covered with fine sand. Grain sizes that are too large (coarse gravel) will block the advance of its very delicate underground runners, preventing it from carpeting the bottom.

Water Chemistry: Relatively plastic, it prefers soft to medium waters (GH 4-10) with a slightly acidic or neutral pH (6.0 - 7.0), typical of high-tech tanks with aquasoil. The optimal temperature is around 20°C to 26°C. The use of remineralized reverse osmosis water is highly recommended to prevent calcium buildup on the needles, which would block the stomatal pores.

Space Management and Placement: The undisputed queen of the foreground. It is the absolute easiest carpeting plant to manage compared to *Glossostigma* or *Cuba* (HC). It must be planted by dividing the original pot into tiny tufts of 3-4 needles each, spacing them in a checkerboard pattern a couple of centimeters apart: within a month, the runners will fill the empty spaces, creating an uninterrupted carpet.

Trimming: Compared to *E. parvula* (which must be mowed because it reaches 10 cm), Eleocharis "Mini" is a zero-maintenance or near-zero-maintenance plant. It spontaneously stays below 5 cm. Pruning is rarely required, just once or twice a year to cut away any old yellowed needles with curved scissors and stimulate total cellular renewal, bringing it back down to ground level.

Risks and Diseases: Its bitter enemies are benthic algae and detritus buildup. The very thick fuzz of the lawn traps fish waste (mulm), which, by rotting, suffocates the basal leaves and triggers explosions of cyanobacteria or black beard algae (BBA) on the needles. It is crucial to have a flock of Amano shrimp (Caridina multidentata) and good ground-level flow to keep the blades clean and free of epiphytic parasites.