The Water Cycle
Water in a Pool
Treatments outlined here are by no means the only ones available. Other treatments are being developed, such as chlorinated isocyanates, bromide treatments and UV filtration.
Developing Treatments include:
Sodium bromide plus hypochlorite;
Sodium bromide transfers to hypobromous acids, but sodium bicarbonate and sodium hexametaphosphate must be added as a buffer to minimize chlorobromines. The theory is the same as for sodium hypochlorite, but this time, the levels of total bromide are important.
TCDO plus Siliceous Aluminate;
Siliceous aluminate (an anionic coagulant) is pumped into pre-filtration, followed by the cationic coagulant. The TCDO complex, (Cl4O10)- is dosed post filter and it reacts with the free chlorine to give a low free chlorine level. The TCDO complex doesn't react with the ammonia, but enables the levels of chloramines, dissolved solids and trihalomethanes to be minimized. It is claimed that the two coagulants together improve filtration and allow less frequent backwashing.
Silver and Copper ions have been used to clean pools for years. In recent times, they are not enough to maintain clean water in a high bathing load. Silver works as it has a slow inhibiting effect on bacterial growth, whilst copper is an effective algaecide but causes a green / black staining colour. Evidence for the overall effectiveness of this method is not wholly convincing.
This is a non-halogen disinfectant. It inactivates micro-organisms but does not oxidize the pollution from bathers. Research is currently being done on the use of this as a compound, but it is not recommended for use in non-domestic pools as yet.
Zeolite materials such as clinoptolite have been marketed as a replacement for sand in a pool filter. The theory is that the zeolite removes ammonia, such as in the form of chloramines. The case is still unproven.
The idea is that by placing magnets around the pipes circulating the pool will help normal disinfection by a form of synergy. Evidence for this is somewhat limited!