Plants and Wildlife
Clear water and healthy plant and animal life in the pond rely on achieving a biological balance in the pond. Factors that control this are: water volume, surface area of water, aeration, sunlight, plant life, animal life and decomposing debris.
The pond pump and filter clean and aerate the water.
Floating plants help to limit excessive light levels in the water. Plants help to oxygenate the water.
Fish, amphibians & molluscs feed on insect larvae & algae
High light levels, high levels of nitrates in the water (especially tap water) and high temperatures may encourage formation of floating algae and blanket weed (algal strands). Overfeeding fish can further nitrify the water encouraging algal growth.
Excessive faeces from overstocking with fish can reduce oxygen levels in the water as waste breaks down. Leaf litter and debris building up the bottom of the pond reduce oxygen levels in the water as waste breaks down and can lead to stagnation of the water. Over colonisation of floating plants or floating fallen leaves can reduce light levels too far in pond leading to poor plant and animal health.
Waterlilies etc. are planted in baskets. Initially these should be placed in shallow water. As they mature they should be moved down to the deeper part of the pond.
Floating plants will increase through the growing season. Do not allow them to cover too much of the water surface. They will probably die off in the winter. Aerating plants are free floating in the water. Do not remove these when cleaning the water with a net.