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.
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.
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.
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.
Hydrogen peroxide is especially effective against green algae and blue-green algae (cyanobacteria). It is heavier than water and sinks to the ground, which is useful if you're dealing with algae near the ground and somewhat of a hindrance if the algae are higher up in the tank.
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.
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.
Chemical treatments: You can fight algae growth in your water tanks by using bleach or chlorine. Bleach kills algae and prevents it from growing. The appropriate amount is ¼ teaspoon for every gallon of stored water. Chlorine will also kill algae and keep your water safe for drinking or irrigation purposes.
Your Best Weapon Against Algae
Chlorine—yep, your typical sanitizer—is much more effective at killing algae than algaecide is. Even if your water gets cloudy and your walls get slimy, chlorine can still kill it. That's because chlorine oxidizes bacteria and single-celled algae, which means they trade electrons.
Pool chemical measurements are based on 10,000 gallons of water. If your pool is larger or smaller, you'll need to adjust your math. A rule of thumb is 1.5 lbs. of baking soda per 10,000 gallons of water will raise alkalinity by about 10 ppm. If your pool's pH tested below 7.2, add 3-4 pounds of baking soda.
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.
Prevent harmful algal and cyanobacterial blooms from forming
Use only the recommended amount of fertilizers on your farm, yard, and garden. This will reduce the amount of nutrients running off into nearby water bodies. Nutrients in the water can help algae and cyanobacteria to grow more quickly than usual.
Apply a mustard algaecide following the label directions. Allow the water to circulate for 24 hours. Use a pool vacuum or backwash the pool again to remove the remaining dead algae. In persistent cases, brush the pool and apply algaecide once more after two to four days.
Yes, dilute apple cider vinegar (ACV) is a great choice for combatting algae in your bird bath the natural way. The higher pH value of the ACV makes it too acidic for algae to grow. The typically suggested ratio is 1 tsp ACV per gallon of water.
Water Changes.
Water changes dilute and remove dissolved organic compounds in the water that promote nuisance algae growth. It is a good idea to use a gravel vacuum to remove dissolved foods etc from the sand bed.
Zinc and copper ions, even in very low concentrations, will kill algae.
Only algaecides can "kill" algae in pool water. However, baking soda can help clear up algae. Use both so you can restore sparkly, clean water!
But common pantry essentials that are often used for cleaning — like baking soda and vinegar — shouldn't be mixed either. Unlike the bleach-ammonia mixture, combining soda and vinegar won't hurt anyone — but don't expect the mixture to do a good job cleaning, either.