Particulates will either need to be broken down by oxidizers, bridged with cationic coagulants for the filter to remove, or heavy enough to drop to the pool floor with flocculants. Coagulants, since they are slow acting, should be used as soon as water begins to haze, or even in regular maintenance to stop problems from forming. A flocculant, which can only be used in pools that allow vacuuming to waste, is meant to treat extreme cloudiness. They are effective in getting rid of dead algae following algicidal treatments. Water restoration is quicker, but vacuuming is necessary to remove material from the bottom. This keeps flocculant usage limited to sand or some DE filters if the manufacturer recommends.
Coagulants can work wonders for both preventive and curative treatments, but often take time to improve. In many instances, the mechanisms of coagulants and flocculants occur in succession. Coagulation neutralizes the negative charge on contaminants to bind them together into small clumps that are more manageable for the filter, whereas flocculation binds them into heavier and larger clumps that will eventually separate from the water.
Although these particles are larger, it is still unlikely to see them with the naked eye. What will be evident is clearer water surrounding the weighted particles. This reveals the contaminant charge has been neutralized for the flocculant mechanism to take place and drop out the particulates. Aluminum-based salts are high performing flocculants and clarifiers that function under most chemical balances. Some commercial flocculant materials may require more dosages and pH alterations.
Coagulants are commercialized in two forms: natural and synthetic. Both have similar and efficient mechanisms, but many pool operators might prefer one over the other. For a more natural route, chitosan is an option. In addition to the aquatics industry, it is used by many others including pharmaceutical, biochemical, cosmetic, and water treatment.
Chitosan is produced by extracting chitin, the supportive material of crustaceans recycled from the food preparation industry. Through some chemical processing, this biodegradable polysaccharide chain of glucosamine and a positively charged amino group becomes chitosan. It has a carbohydrate structure not unlike cellulose. It floats along the top few layers of the water where it seeks attractive contaminants such as oils, metals, or dirt to neutralize their charges and coagulate them into larger clumps for better filtration. Unlike some remedial products, chitosan will function regardless of the water chemistry and will not be impacted by sanitizer residual.
