When the pH is lower than 7.2, the chlorine becomes extremely inefficient and is rapidly depleted giving off a strong chlorine smell.
You should always adjust your pH levels before adding chlorine to the pool. The ideal pH level is between 7.2-7.6 and having a high pH level (above 7.6) will make [...]
It can take up to 24 hours for the chemicals to balance in a pool.
You should test your pool weekly during the swimming season and fortnightly during non-swimming season (autumn/winter).