Saline water is readily available in coastal communities, yet evidence on its suitability for curing concrete remains limited. This study reanalysed rebound-hammer measurements on 150 mm concrete cubes produced with a nominal 1:2:4 mix and a water–cement ratio of 0.60 and cured in borehole water from Otuoke and saline water from Korokorosei, Bayelsa State, Nigeria. Rebound numbers were recorded at 7, 14, 21 and 28 days. Specimen means were recalculated from the individual readings, and the two-curing media were compared using Welch tests with Holm correction, Hedges’ g, exact permutation tests, a split-plot analysis of variance and a logarithmic age model. Rebound number increased with age in both media. The saline group was about 13% higher at 7 days, but the difference remained below 2.5% at later ages, and no age-specific difference was significant after correction. Curing age accounted for most of the variation, whereas the interaction between curing medium and age was not statistically significant. An apparent decline in hammer-derived strength at 21 days was traced to an arithmetic error in the computation of the group mean. The findings are constrained by the small number of specimens per group, uncertain independence between specimens across ages, the absence of water-chemistry data and undocumented hammer calibration. The results indicate an early difference in surface hardness but provide no evidence of equivalent compressive strength, durability performance or a confirmed curing-medium effect.
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