Ponds on farms can have several purposes. They may provide water for cattle or other animals, be used for fishing or to breed fish, theycould be a swmming hole or they may be built purely for beauty.

A pond can enhance your property adding to its aesthetic appeal. Photo supplied.

If building a pond from scratch, the work begins with proper planning. Decide on the purpose of the pond, the size you will require and the prospective site. Check with council if planning or resource consent is needed and perhaps consult with an engineer or pond construction expert on soil suitability and the best way to go about creating a pond.

When considering the best site, especially if you plan to have fish in the pond, avoid close proximity to trees, in particular oak and various pines, which are poisonous to ponds.

The amount of sediment, which can build up when trees shed their leaves can increase PH levels to the detriment of fish. There may also be an increase of algae-friendly-nutrients that can lead to a host of problems. 

Placing a pond on land that is too low-lying is usually to be avoided. Run-off water during heavy rains carry all manner of unwanted material, fertiliser and toxins, which will accumulate in the pond.

However, some pond managers suggest that if you require surface water to help maintain pond levels then building too high may not be the answer either. This is where expert advice should be sought.

Soil quality may also influence pond placement. If placing your pond in an area with sandy, free draining soil, water leakage is likely.

You are better to choose an area where water can be locked in without much effort needed to seal boundaries. Alternatively, a lining of clay will help prevent water leakage.

Remember to determine the source of the farm pond’s water supply. The water may be sourced from wells, springs, bores or even the surface.

Ponds that gather water from the surface require a watershed or drainage system and it should be big enough to sustain the water level especially during the dry season.

If planning to stock the pond with fish, purchase varieties which require little attention.

Avoid over-stocking in order to give fish the best chance of survival and ensure the pond is well planted with native aquatic plants which  adapt easily to the environment and require minimal maintenance. Reject invasive spreading plants, such as water hyacinths.

Bear in mind a proper depth of water is required to ensure fish and other pond life have enough throughout the seasons.

In summer deeper water will be a blessing for fish as they don’t like direct sunlight. The lower layers of water will be cool and aquatic floaters will also give surface shade.

A well-balanced pond can survive easily without too much interference and if it has a variety of aquatic plants, rocks, stones, fish, it should maintain itself as a balanced ecosystem.

Without all those things, and certainly while the pond is becoming established, biological, UV and mechanical filtration will be necessary.

Without them “gunk” will build up with algae, excess nutrients and harmful bacteria bringing all their attendant problems.

Monitor the levels of ammonia and nitrates in the water on a regular basis and use a biological filtration unit. An ammonia neutraliser chemical may be required every now and again.

Installing a fountain or waterfall is a simple way to aerate the water, but ensure the pump is protected from debris. Use a good quality filter.

If you have any pond issues seek the advice of an expert and remember good pond maintenance starts with a sound plan and continues with a regular inspection programme.