Polygonium sp. Pink:
Overview: More popularly called as Persicaria (or Polygonum) sp. ‘Kawagoeanum’ this plank makes an excellent aquarium plant for both beginners and experts. It is from East Asia and grows perfectly in wet places like riverbanks, ditches, and bogs. The plant thrives well in above as well as below the waterline. Since this plant has not made enough popularity among the aquarists, the availability is generally rare. The plant is easy to grow and maintain. It doesn’t require much care and can flourish well in low-tech aquaria. Polygonum sp. “Pink” most of the time is confused with Polygonum sp. “Sao Paulo” and sold under that erroneous name as well, therefore, needs special attention while picking the right one.
 Appearance: Polygonum sp. “Pink” is not strictly upright like other knotweed species which are widely used as aquarium plants. However, it spreads and ramifies at short durations. It leads the plant to develop a dense bush. The best part is this bush is easy to maintain and doesn’t create any hindrance for the fish. If you want your aquarium to get Japanese-style nature aquarium outlook, this plant is perfect to choose. The plant has the tendency to lose the lowermost layers of the leaves.
Hard/soft plant: Hard plant
Ideal water temperature: It requires a temperature between 20 to 30 °C.
Lighting conditions: This plant requires strong light. Metal halides, T5s or power fluorescent bulbs make great options to ponder to provide the needed light. If the plant gets intense sunlight or you provide deep artificial lighting leaves show chevron-shaped markings that make the plant look even more attractive.
Ideal pH Level: pH between 5 and 7.5 is considered perfect for the plant.
Do you know: When Polygonum sp. “Pink” grows in combination with Cyperus helferi; the aquarium gets a very attractive look as both plants complement each other. Both make perfect background plants for different sizes of aquaria.