+1.. much of this is dependant on the parameters of your source water. Buffer life will likely last longer if the buffering is a lesser swing. the buffering should start happening immediately but would be only measureable if the change is larger. For reference, my tanks with flourite, ecocomplete and safe-t-sorb all reside within 6.5-6.7. FSS tends to remain in 6.6 for the past 7 months.
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