Any time that a new pool finish has been applied or the pool has been emptied it is necessary to add the proper chemicals to bring the water into balance. The parameters for properly balancing water is available from organizations like the APSP and the NPC.
New pool finishes can have a dramatic impact on the quality of the water due to the hydration process of the cement. While the cement continues to hydrate and harden it releases calcium hydroxide which transforms into calcium carbonate with elevates the pH and alkalinity levels in the water. If left untreated these elevated levels can have serious detrimental effects on the new finish that can be un-reversible.
A proper Start Up procedure protects and preserves the new pool finish and facilitates a longer service life with greater aesthetic appeal.
“The pool finish will start to hydrate immediately after mixing, with the majority of hydration taking place within the first 28 days. This critical time period is when a finish is most susceptible to staining, scaling and discoloration. Proper start-up procedures including timely brushing and constant monitoring and adjusting of the pool water is mandatory. The following recommended start-up method is based on procedures shown to produce the best aesthetic results. Due to unique local water conditions and environmental factors, parts of these recommended start-up procedures may need to be modified to protect the pool finish. For example: filling the pool with extremely low calcium hardness, low pH or low total alkalinity levels may necessitate changes to these procedures. Brushing and monitored chemical2 adjustments will be mandatory by the homeowner or a trained pool technician during the service life of any pool surface.” National Plasterers Council, NPC Start Up Card, September 2012 edition