Hq40d portable multi meter

Water salinity (21.1–29.5‰), pH (7.81–9.18), and temperature (23.7–26°C) were measured (Hach HQ40d Portable Multimeter, Loveland, CO) daily around 11:00 by the animal caretakers and this data are provided in Appendix 1. Air temperature (kept between 24°C and 28°C) was regulated by means of air‐conditioning and ventilation at the top of the roof, while relative humidity (± 70%) was controlled by means of water sprayers.

Automated controls of seawater temperatures were provided by SeaSim via the SCADA (Supervisory Control and Data Acquisition) system. Seawater temperature of each tank was monitored hourly using resistance temperature detector (RTD). To confirm the treatment conditions inside the 6-well plates (i.e., where the larvae were located), seawater that was removed from the wells during water change was collected for measurement of O₂ level, salinity, temperature and pH every day at 12:00 using the HACH HQ40D Portable Multi Meter. Salinity measurements were calibrated with IAPSO Standard Seawater. Seawater from several wells of the same tank was combined for measurement due to depth requirement of the measurement probes. Total alkalinity (A_T) was measured twice during the 10-day experiment using VINDTA calibrated to Dickson’s Certified Reference Material. Ω_arag (aragonite saturation state) and DIC (dissolved inorganic carbon) were calculated using the measured values of seawater A_T, pH, temperature and salinity, with the program CO2SYS⁹⁸ as implemented in Microsoft Excel by Pierrot et al.⁹⁹ .

When all samples had been taken, the bulk soil samples were thawed and air dried for 48 h, disaggregated, and allowed to air dry again to reach a constant mass. Each sample was weighed and ground to pass through a 2-mm sieve, with any material not passing through weighed and discarded. The remaining material was then all ground to pass through a 355-μm sieve to improve sample uniformity and amalgamation. SOM was then determined by the Walkley-Black dichromate method (Walkley and Black 1934 ). Plant available P was determined using Olsen’s reagent (Olsen et al. 1954 ) and measured colorimetrically in solution by spectrophotometry using the molybdenum blue method (Murphy and Riley 1962 ). Soil N content was determined as Total Kjeldahl Nitrogen (TKN) using the method 4500-N_org Nitrogen (Organic) (Standard Methods for the Examination of Water and Wastewater 2018 ) with a 50:1 dilution of water/soil, copper catalyst tablets (Fisher Scientific, 1g Na₂SO₄ and the equivalent of 0.1g CuSO₄, Fisher chemical K/0120/80), a Buchi B-435 Digestion Unit, and Buchi B324 Distillation Unit. pH was measured using a 1:2.5 v/v suspension in water (World Agroforestry Centre 2014 ) using a Hach Intellical PHC201 pH electrode and Hach HQ40D portable multimeter.