This lax, straggling, dingy, dark green pleurocarp lacks red tones. Its leaves are always curved, but seldom very strongly so. This and its long, irregular branches give W. fluitans a distinctive appearance. Rhizoids are sometimes produced on the leaf tip. Shoots may be many centimetres long, and leaves are 3 to 5.5 mm long. Curved, cylindrical capsules occasionally form, borne on a seta about 4 to 8 cm long.

Typical of nutrient-poor, base-poor, still water, especially pools fed by rainwater in the uplands.

All year round.

Widespread and fairly frequent in Britain.

Status in Leicestershire and Rutland not known.