Potamogeton crispus

Potamogeton crispus is found across Europe, Asia, and Australia in cool lakes, ponds, and slow rivers. Its narrow leaves have a strongly undulate, crinkled edge and a semitransparent texture that catches the light attractively. In autumn it produces turions (overwintering buds) that sink and lie dormant before regrowing in spring — a seasonal cycle that makes unheated aquariums interesting year-round. It is one of the most cold-tolerant aquarium plants available, thriving in near-freezing conditions.

Light: Medium (25–50 PAR); performs well under standard or moderate aquarium lighting in cool water. CO2: Not required; low-tech setups are ideal for this temperate species. Planting: Plant stem groups in the background; 5–7 stems per group spaced 8–10 cm apart. Maintenance: Trim tops as they approach the surface; collect turions in autumn and store cool if dormancy occurs. Note: A strong seasonal plant — may die back in summer heat above 22°C and regrow vigorously in cooler conditions.