Algae can be troublesome and enigmatic, but out of all the different types, a pond owner dreads filamentous algae the most. This type of algae is the most common and reproduces at a fast rate and floats at the surface of your pond. Anyone who owns a pond will easily be able to distinguish filamentous algae because of its distinctive mats which resemble strands of hair. Filamentous algae are unattractive and if your pond is infected with it, it will unsightly eyesore.
Upon your initial inspection, you may assume that filamentous algae float by themselves and consist of a single cell. This is partly true, while they do consist of only one cell; filamentous algae don’t like to be alone. This is where the comparison to dense strands of hair comes into play. These strands hang out at the surface of a pond. Three types of filamentous algae are spirogyra, cladophora, and pithophora.
Spirogyra is not hard to recognize because its shade of green is so intense it appears to be glowing. This species of algae looks like a DNA helix when examined under a microscope. In the environmental conditions of a pond, it is extremely slippery and normally enveloped with a concentrated frothy protein residue. Cladophora has a cottony appearance and is found in the shallow areas of a pond. This type of algae looks like very little plant stems that oscillate and appear fuzzy. Pithophora develops into lengthy strands that are dense. It is commonly referred to as horse hair because of this and has a wooly texture.
Filamentous algae will initially be detected in the shallow areas of your pond. If your pond has a very little amount of filamentous algae, there will likely be no threat to your pond. Filamentous algae become unmanageable and multiply if your pond has elevated levels of nitrates. These nitrates provide nourishment for the algae. If left alone, filamentous algae will grow at a fast rate and your pond water will be a very unattractive shade of green.
When the algae take over the bottom of your pond, it gives off vast amounts of oxygen as it multiplies. The oxygen can’t escape the concentrated masses, and will ultimately come to rest at the surface of your pond. Your pond will be covered with these buoyant green masses, if remained untreated.
To keep filamentous algae under control, your pond should have an adequate supply of plants and a if possible a filtration system that operates well. Adding plants to your pond will provide shade and vie for oxygen and nitrates, just as algae. Another way to remove filamentous algae is by simply removing the top layer with a rake or net. A vacuum can then be used to get rid of the algae at the bottom of smaller ponds pond. Algaecides can also be added to your pond to eliminate filamentous algae.
Always consider a good pond bacteria designed to digest the sludge layer typically found in older ponds. Sludge plays an important role in storing and supplying high nutrient levels vital to the survival of most algae. Bacterial digestion of pond sludge and scum layers will enhance the pond natural ability to remove waste and nutrients vital to the growth of algae.
By: Bradley Skierkowski