Myriophyllum pinnatum

Myriophyllum pinnatum is a fast-growing North American milfoil featuring olive-green to mid-green pinnate, comb-like leaves arranged in dense whorls along long stems. It excels at nutrient export in heavily stocked or high-tech planted aquariums and provides dense mid-to-background cover for fish and invertebrates. Under strong lighting with CO2 supplementation it produces particularly vigorous, lush growth and can take on reddish tints.

Plant in groups of 5–7 stems in nutrient-rich substrate. Provide moderate to high lighting; CO2 injection significantly improves growth rate and plant quality. Trim stem tips regularly to encourage lateral branching. Replant robust top cuttings to maintain a full background.