This plant comes from Southeast-Asia is a weed in the wet rice fields over there and found in tropical waters in other parts of the world in the meantime. The plant is very like the closely related Rotala rotundifolia, but differs in the pink flowers which appear with T. indica in small spikelets from the leave-axils. The tiny, oval, ab. 2 cm long, green leaves occur in opposite position on the slender, fragile stems. They show thick, whitish margins and colour yellow to red when sufficient light is available. A fast and bushy growing plant. Fish like to nibble of it.