Tricks to Prevent Green Pond Water

1. Don’t overstock your pond with fish

Anyone can appreciate that fish are captivating pets and features to keep in a garden pond. Fish bring an exciting fusion of colour and movement to ponds, help to reduce insect infestations, and for many, they’re very therapeutic to gaze at.

If you opt to populate your pond with fish, after choosing the best fish to add to your pond, you need to select a suitable fish load, as too many fish can leave your pond destined for disaster!

This is down to the fact that the more fish there are, the more natural biological processes are taking place in the pond. For example, there’s more faecal waste being produced that provides the nutrients required for green water to occur.

2. Don’t overfeed your fish

Adding more fish food than necessary can affect your pond’s water quality and lead to green water problems – not only from the natural biological processes of your fish, but also from the food that isn’t consumed.

If you’re unsure about whether you’re overfeeding your fish, you’ll need to do some research, as it’s not a ‘one size fits all’ answer. Pond size, fish type and quantity, and temperature and aeration in your pond all play a part in how much you should feed your fish.

What happens to fish food that’s not eaten?

Leftover fish food decomposes in pond water, releasing phosphates that fuel algae growth and as a result, green water. If you notice that your fish aren’t eating all the food you give them, reduce the amount you feed them to make sure there’s nothing left behind.

This is most likely to occur in your pond during winter months when fish have a reduced appetite and aren’t feeding as much.

3. Provide some degree of shade to your pond

The algae that cause green water are plants, and just like any other plant, they love sunshine. This is bad news for any pond that isn’t sheltered from direct UV light from the sun.

Building a pond with shade isn’t always ideal, but there are still ways of providing some degree of cover to it – such as using aquatic plants.

What pond plants are good for shade?

Floating pond plants, such as water lilies, are a great method for controlling algae growth. They provide partial shade to reduce sunlight exposure not only to algae, but also to fish such as koi, which can be sensitive to sunburn. There are several floating plants to choose from depending on your desired aesthetic, including:

– Marsh marigold

– Water lilies

– Water hyacinth

– Water forget-me-not

– Water mint

– Water lettuce

4. Use beneficial bacteria

As mentioned before, green water is caused by single-celled plant organisms called algae. This organism typically occurs when there is an imbalance (high amount) of nitrates and phosphate levels in pond water providing algae with the nutrients to grow and in perfect conditions, thrive! These nutrients are elevated via some of the points mentioned above, however, can be eliminated with the use of a beneficial bacteria treatment, such as Pond Klear and Filter Feed.

Pond Klear works by binding together and consuming the green algae particles, along with all the fish waste, dead leaves and organic matter that form the algae’s source of food. Pond Klear, therefore, prevents green water algae from growing.