Nutrient data collected from experimental tanks observing the effect of nutrient pollution on Acropora cervicornis disease susceptibility from 2020-09-14 to 2020-11-13 (NCEI Accession 0278916)

This dataset contains the nutrient results for an experiment that assessed the effects of elevated NH4 on corals disease susceptibility. Eleven Acropora cervicornis genotypes were selected to conduct a full factorial tank. Replicate coral fragments (n=24 per genotype) were obtained in July-August 2020 from three South Florida coral nurseries and allowed to recover in tanks in the University of Miami and NOAA’s Experimental Reef Lab (ERL). After recovery from handling, the fragments were evenly allocated to one of eight independent tanks at ERL. For a month and a half, four tanks were maintained under ambient nutrients consistent with nutrient levels present in the seawater from Biscayne Bay, and four tanks were exposed to a 10 μM increase in ammonium concentration (n=12 fragments per genotype per nutrient treatment). To achieve and maintain the nutrient concentrations in the elevated ammonium tanks, a stock solution of NH4Cl was constantly added using peristaltic pumps (~ 10 mL of NH4Cl [2.25 mM] every 15 minutes) to replenish nutrient levels and account for the income of new water in the tanks. After 47 days of nutrient treatments, half of each nutrient cohort was challenged with a disease slurry and half with a placebo slurry, and signs of disease were monitored daily.

NH4 concentrations were monitored approximately twice a week, and other nutrients (NO2, NO3, PO4, and Si) were estimated for a few time points. Water samples (~ 40 mL) for nutrient analysis were either preserved with 0.5 mL of Chloroform or were frozen until they were processed in the laboratory. The samples were always analyzed for ammonium on a SEAL AA3 Autoanalyzer following EPA methods and NELAC standards. For a few time points phosphate, nitrate+nitrite, nitrite, and silicate were also estimated.