Overview Reef Builder™ raises carbonate alkalinity (KH) without immediately impacting on pH. With long term use there will be a tendency to stabilize at pH 8.3. Used as directed, Reef Builder™ will not deplete calcium, magnesium, or strontium which usually tend to precipitate with increasing alkalinity. Reef Builder™ and Reef Buffer™ may be used together. Use Reef Builder™ to raise carbonate alkalinity without affecting pH. Use Reef Buffer™ to raise carbonate alkalinity and pH. Reef alkalinity should be maintained at 3–5 meq/L (8–14 dKH). Alkalinity should not be allowed to fall below 2 meq/L.