Calanus glacialis were collected from Rijpfjorden, Svalbard (European Arctic) in order to investigate the effect of lowered pH on their physiology, as a predictor of the effects of ocean acidification. Eggs were cultured through nauplis stage N6 over 35-38 days at 4 pHs (8.05, 7.95, 7.7, and 7.5) with three replicate tanks per pH. Two samples (or 10 pooled nauplii) per tank were collected for mRNA sequencing.