Chlorine gets a bad press but since it was discovered that chlorine kills germs its use as a sanitiser in drinking water has saved millions of lives worldwide. Chlorine is the only chemical that acually kills algae.
Chlorine is still one of the most effective killers of algae so doing a super-chlorination of 10-20 ppm of chlorine can go a long way towards wiping out the algae. Liquid chlorine is an ideal shock for algae because it is fast acting and does not add cyanuric acid (CYA) or calcium to the water.
Bleach is great for killing algae (and other organisms that may lurk in your tanks) and for keeping it from coming back.
Shock Your Pool
Shocking is the process of adding chemicals to your pool to raise chlorine levels and kill bacteria and algae.
Black algae is a stubborn organism. Its protective outer layer sets roots into the surfaces it clings to. This makes it one of the toughest algae strains to get rid of.
Barley straw is a natural way to fight algae. On contact with water, the straw starts to break down, and as it does so it releases peroxides into the water which combat algae. Available in mini bales, or as a concentrated extract of barley straw liquid, it's a natural way of chemically fighting algae.
StoneCare4U Essential Algae Remover is a safe and easy way to remove algae from any 'hard' external surface. Its biodegradable formula can be used on a multitude of outdoor surfaces including paving, walls and roof tiles.
Use White Vinegar to Remove Algae
If you have an algae problem, your best friend is white vinegar. White vinegar can quickly kill algae but is not harmful to birds, insects and the majority of plants. Use a mixture of one part water to one part white vinegar to spray down the area and kill the algae.
Q-Clear® is a powerful and fast acting biocidal product used for quickly killing and removing algae, mildew, lichens, moulds and fungi from all external hard surfaces.
When added to water containing algae, H2O2 breaks down into water and oxygen, releasing free oxygen radicals in the process. These free oxygen radicals can then react with and destroy the cell walls and membranes of algae cells, causing them to die off.
CuSO4 is the chemical formula for Copper Sulphate. It is used as a fungicide, algaecide, root killer and also used as an antimicrobial. It is the chemical that is generally used for controlling algae.
Sodium Percarbonate is an excellent killer of bacteria, fungi, various viruses and mold, so it can be used as a very effective agent for removing algae and moss.
TIP 5: USE BLEACH OR VINEGAR
Oxidized bleach immediately starts to kill algae cells once it comes into contact with it. Bleach, however, should not be your first option, especially if the area you plan to rid of algae is near plants or grass.
Bicarbonate, the active ingredient in baking soda, is an effective spot treatment to help kill the algae and loosen it from the wall. Make sure you really get every last particle free; black algae has particularly long and stubborn roots which makes it a persistent strand.
But as it turns out, copper pennies do a pretty good job of keeping algae away for a few days! Pennies made before 1982 contain copper and according to Google, “copper kills algae by binding to it, which damages the algae cells, causing them to leak and die.” I tossed in 10 pennies and waited for the results.
Hardware stores and home centers sell products designed to kill moss and algae, but you can save money by using inexpensive chlorine bleach or a non-creamy hand dishwashing detergent, such as Dawn.
I've had fantastic success cleaning algae from just about every outdoor surface using liquid dish soap and my favorite exterior cleaning brush. This brush is one that's made to clean RVs. It's got lots of bristles that are about 2.5 inches long and they're soft.
Excess nitrogen and phosphorus cause an overgrowth of algae in a short period of time, also called algae blooms. The overgrowth of algae consumes oxygen and blocks sunlight from underwater plants. When the algae eventually dies, the oxygen in the water is consumed.
Rowan said white vinegar is also a "practical and effective way" to remove algae from outdoor tiles. He continued: "Simply spray it onto the algae and let it sit for less than an hour. "Once it has penetrated the spot, the acidity will break down the algae, then scrub the surface with a stiff-bristle brush.
Another chemical-free solution that you can consider is a mixture of baking soda, water and vinegar. Add two parts of white vinegar to one part of water and three heaped spoons of baking soda. Dip a scrubbing brush into the mixture and apply it to the algae stains on your furniture. Leave it for about ten minutes.
There are products that incorporate compounds of ammonia used to remove algae and clean-up water. Two products for algae are quaternary ammonium and poly-quaternary ammonia used to fight against green algae. Both of these products incorporate an ammoniated compound that serves to lower the water surface tension.
In the case of blue-green algae: Use 1.5 to a maximum of 2.5 ml of the 3% solution of hydrogen peroxide per gallon of water. In the case of green algae: 20.25 ml to a maximum of 32.5 ml of the 3% solution of hydrogen peroxide per 13 gallons of water.