I have some hard corals, clownfish, brittle stars, gobies, chromis, and a watchman tang in a 55 gallon tank
pH drops to 7.95--then I add buffer and get it to 8.1--8.14. Two days later it is back down to 7.95. I add fresh seawater at least once a week (5 gallons at a time) from 5 miles...