Potamogeton natans, commonly known as Broad-leaved Pondweed or Floating Pondweed, is an aquatic plant species found in various freshwater habitats, including ponds, lakes, and slow-flowing rivers. It is characterized by its broad, oval-shaped leaves and ability to float on the water's surface.

Here is a detailed description and care guide for Potamogeton natans:

Description:

Potamogeton natans features long, slender stems that can grow up to 3-6 feet (90-180 cm) in length. The leaves are large and oval-shaped, measuring around 1-3 inches (2.5-7.5 cm) in length. The leaf colour can vary from dark green to reddish-green, providing an attractive contrast in the aquatic environment. The plant may produce small, inconspicuous flowers that emerge above the water's surface.

Care Guide:

Lighting: Potamogeton natans requires moderate to high lighting conditions. Provide at least 2-3 watts per gallon of full-spectrum light to promote healthy growth.

Water Parameters: Maintain a water temperature between 18-28°C (64-82°F). The pH level should be slightly acidic to slightly alkaline, ranging from 6.5-7.5. The water hardness can vary, but a range of 3-10 dGH is generally suitable.

Substrate: Potamogeton natans can be grown with or without a substrate.
If grown without substrate, the plant can be anchored using weights or placed in mesh pots filled with aquatic plant substrate or clay. If grown with substrate, a nutrient-rich substrate can help support its growth.

Nutrient Requirements: Regular fertilization is important to provide essential nutrients to Potamogeton natans. Liquid fertilizers or root tabs can be used to supply macro and micronutrients. Carbon dioxide (CO2) supplementation is not necessary, but it can promote faster growth and denser foliage if desired.

Water Flow and Oxygenation: Moderate water flow is ideal for Potamogeton natans. It helps distribute nutrients and prevent debris from accumulating on the leaves. Adequate water movement also promotes oxygenation, benefiting both the plant and aquatic organisms.

Propagation: Potamogeton natans can propagate through runners or by planting stem cuttings. Healthy side shoots or stems can be trimmed and replanted in the substrate or floated on the water's surface to develop new plants.

Compatibility:
Potamogeton natans is generally compatible with a variety of fish and invertebrates. It provides cover and spawning areas for fish and serves as a habitat for aquatic organisms. However, be mindful of potential herbivorous fish that may nibble on the leaves.

Regular maintenance, including trimming and nutrient supplementation, will help maintain the health and appearance of Potamogeton natans. Monitor the plant for any signs of nutrient deficiency or excessive growth, as well as the overall condition of the aquarium or pond. With proper care, Potamogeton natans can create a natural and visually appealing aquatic environment.