Nuttall's mudflower

The plant sold under this name is not the real Micranthemum micranthemoides. That species grew in tidal zones along the mid-Atlantic coast of the United States and has not been seen in the wild since 1941. What fills the pots at aquarium shops is Hemianthus glomeratus, Manatee mudflower, which comes from Florida and is still common in its native wetlands there.

Underwater it forms thin, branching stems set with small oval leaves in whorls of three or four. Given decent light it stays compact and bushy in the foreground or midground, making a mass of fine vegetation without the creeping runner system that carpeting plants like Hemianthus callitrichoides rely on. In lower light the stems stretch vertically and the internodes lengthen.

It is not demanding. Temperatures from 24 to 26 °C and pH 5 to 7.5 cover most community tanks, and it grows well without injected CO₂, though adding it produces denser, bushier growth. A regular supply of nitrate and phosphate keeps the stems robust. Greyish deposits on the leaves indicate CO₂ deficiency, not disease — this species is prone to biogenic decalcification when carbon runs low.

Propagation is by cuttings. A stem trimmed and replanted roots quickly, and the parent branches from the cut point, so frequent trimming thickens the clump. It is also one of the easier foreground plants to keep in a nano tank.