There are several types of algae that can be found at times in the fresh water aquarium environment, but very rarely will they be found together at the same time in the same tank. These algae can be separated into the following main groups:
- Unicellular Green
- Filamentous Green
- Blue Green
Unicellular Green algae or ‘Green Water’ normally only occurs in the presence of excess or strong light. If controlling the duration of artificial light (8-10 hours max per day) or avoiding direct daylight does not work, then the biological filter should be checked. Bacteria in the filter will control the algae as it passes through the filter. If the biological filtration has been compromised then action must be taken to rectify this (the staff at AQUOTIX can assist here if required). If all else fails, chemicals such as “Simply Clear” could be used. For repetitive or stubborn problems, you can add a UV Steriliser – see the staff at Aquotix for advice as to which unit will suit your situation the best.
Filamentous Green algae is similar to the above but cannot be controlled by biological filtration as it cannot pass though the filter. There are several forms of these algae, the most common being soft and almost slimy to handle. Many fish such as Siamese Flying Foxes and Mollies happily consume this form. Alternatively, chemical treatments can be used such as “Peroxide” or “Algae Blocks” and the algae are then slow to return, in which case re-dosing may be required. There is a coarser type that grows from one point (rather than free flowing). This form is related to the family of Red Algae (see further).
Brown algae are diatoms that exist in unicellular or filamentous forms. Both forms are normally easily controlled by reducing silica in the water (a requirement for building the diatoms’ cell walls). Silica is found in our tap water, so you will normally see brown algae in aquariums that are newly setup, or have had a lot of recent water changes done. Most Phosphate removing resins (such as “Phos-zorb”) will also remove silica, which is one quick fix.
Red algae, contrary to what the name suggests, can come in many colours from red/brown to dark green and black. The most common red algae is known and described as Black Brush Algae (BBA). Red algae thrive on Phosphates, which enter the aquarium mainly from pH Down Powder (Phosphoric Acid) and fish foods (particularly wafer, tablet foods and frozen bloodworms). There are Phosphate test kits available to find out how high the levels are. The only way to control the growth of this alga is to reduce the phosphates, by reducing the use of the fore-mentioned products and finding alternative products where possible. Phosphate absorption resins (Phos-zorb) and pads (Cut-your-own phosphate filter pad) are available from Aquotix to maintain low levels. For quick reduction of high levels, phosphate precipitation liquids (eg: “Phosvec” or “Phosout”) can be used.
Blue Green algae are not true alga. They are in a family called Cyanobacteria. These are photosynthesising bacteria that leave a smelly blanket of dark green slime over most things. This variety of algae normally appears after doing a large water change on an aquarium with a high Phosphate and Nitrate level. Strong circulation can inhibit the growth and Mystery Snails have been known to eat small amounts of it. Early infestations can be siphoned up before it spreads. If the infestation is severe, the best chemical treatment is ‘Peroxide’. The best way of avoiding this alga is to do regular small water changes and avoid doing ‘Big Spring Cleans’ in one hit, and keeping your Phosphates low.
Overall, most algae come and go. If the algae seem uncontrollable, chemical treatments can be administered without directly harming most fish and plants. The best is to bring a sample of the algae and 100ml of water into AQUOTIX for an accurate identification and expert recommendation.