HYDROS pH 7.0 Calibration Fluid is a single-use, high-precision pH 7.01 neutral reference solution used by virtually every aquarium pH probe and controller. Because pH probes calibrate against two reference points, 7.01 is the neutral anchor included in nearly every calibration — paired with pH 10.0 for reef and saltwater tanks (normally 7.8–8.5) or with pH 4.0 for lower-pH water like calcium reactors and freshwater aquariums. Key details pH value: 7.01 (neutral calibration reference) Best paired with: pH 10.0 for reef/saltwater, or pH 4.0 for low-pH applications Format: high-precision single-use packet Shelf life: store in a cool, dry place for up to 1 year Frequently asked questions Do all pH probes use 7.0 solution? Nearly all two-point calibrations include the neutral 7.01 reference, making it the one solution almost everyone needs. Which second solution do I pair it with? Use pH 10.0 for reef and saltwater tanks, or pH 4.0 for calcium reactors and freshwater. Which controllers use it? Any HYDROS controller with a Probe Port, such as the Control X3, X4, or Launch. Shipped fast with expert support. Get your HYDROS gear from real reefers at Marine Concept Supply, with setup help when you need it and local pickup at our Wheeling, IL showroom.
