Narrow-leaved, overhanging form of Rotala rotundifolia from Vietnam that turns pink-orange to rich orange; with strong light, fertiliser and CO2 it creeps and can form an orange cushion or even a carpet.
Check your local laws. US: Not on Florida's Prohibited Aquatic Plants list (Rule 5B-64.011; Class I/II lists checked), but the species Rotala rotundifolia is a documented invader of canals, ponds and lakes in southern Florida since 1996, probably from aquarium dumping. EU: Not on the 2016 Union list of invasive alien species (later updates not checked). Advice: Never release trimmings or tank water into the wild. Never throw it into ponds, rivers or drains.
14 facts checked with sources