Algae Control in a Pond

Once a pond is established and an equilibrium is achieved between the fish and their surroundings, very little maintenance is required. However, this equilibrium takes some time to be achieved. Algae is the most frequent problem which occurs, by taking advantage of the unbalanced situation. As a rule, algae  have three basic requirements for survival; alkaline water, light and dissolved organic matter (including Nitrates and Phosphates).  Limit or remove one  of these requirements and  the algae will be suppressed or totally destroyed. There are often two types of algae which infest ponds; unicellular algae (green water) and filamentous algae (Blanket weed or Green fairy floss). Unicellular algae can be controlled by limiting the amounts of waste entering the pond, the major source of which is from any fish. The less number of fish in the pond, the less waste entering the pond. Also, waste products can be removed by growing a fair number of plants in the pond. These plants will absorb waste and utilize it as they grow and reproduce. This limits the “dissolved organic matter” requirement of the algae. Another method of controlling unicellular algae, is by supplying a fair amount of shade over the pond, such as with shade cloth or floating plants. This in turn limits the light requirement of  the algae. A third method of control is by filtrating through a UV Steriliser or properly constructed Biological Filter. Bacteria will build up in the filter and eventually overcome the algae. A similar but free-swimming bacteria can also be introduced by purchasing it in a powder or liquid form. This is added regularly as required and will consume the algae. A staff member at AQUOTIX can discuss with you the best method of setting up a filter  for your pond and explain the different products available.

Filamentous algae tends to be a little more resistant to the limitation of its requirements. It’s favourite water condition is alkaline water. This can come about from concrete, limestone, shells, coral and some varieties of stones coming in contact with the water. An AQUOTIX staff member can show you different products and methods for controlling the situation. For larger ponds, Koi carp can be utilized as algae grazers, since part of their natural diet contains algae (though care should be taken due to the Koi’s insatiable  appetite for plants). There is one other method of algae control which will prevent the growth of all forms of algae. This is by means of chemicals. AQUOTIX have several easy to use products  which are effective against typical algae problems. Care should be taken to ensure that the pond does not go foul due to large amounts of decaying algae. Ask an AQUOTIX staff member for tips on using algaecides.

Repotting and/or introduction of  new  plants should be  carried out during spring. This is  the time when plants begin to re-grow from their winter hibernation. They are therefore given all summer to grow undisturbed and store energy  for the next winter. Any excess sludge should also be removed from the bottom of the pond during spring. Waste assimilating bacteria can be added at any time of the year to help consume this sludge in the pond. The reason for doing this is that bad bacteria may proliferate in the organic waste and therefore occur in large numbers at a time when the fish in the pond are attempting to rebuild their strength after the winter. This is when the fish are at their most vulnerable due to their relaxed immune system. If the bacteria are not controlled, it could cause internal bacterial infections. AQUOTIX staff will be able to recognize the symptoms and direct you to the best method of treatment if  there is an outbreak of this or any other disease. Regular water changes are recommended during summer, but never  remove more than half of the water at any one time otherwise you could seriously stress the fish. Always use a tap water conditioner to detoxify chlorine and other chemicals when adding new tap water. Water changes will assist in maintaining the levels of dissolved organic and inorganic matter and also the pH level. During winter this may not necessary due to the amount of rain entering the pond.

If you are unsure about any of the above information or you wish to pursue any problems with your pond, please feel free to discuss this with any of the experienced AQUOTIX staff.