Instant Ocean Aquarium Hydrometer Fritz MarinePure is suitable for both

MarinePure is suitable for both freshwater and saltwater (marine) environments

Dry Run & Overheating Protection

Maracyn® may cause excessive foam production in protein skimmers

For extremely high levels of chloramine or nitrite

Supplied in a state of suspended animation for maximum longevity

Instant Ocean Aquarium Hydrometer Fritz MarinePure is suitable for bothAccurate, reliable water test equipment is absolutely vital to creating and sustaining a healthy, successful marine environment. Easy to read and simple to operate, the Instant Ocean Hydrometer delivers precise full range salinity and specific gravity readings accurate to 0. 001 and does it each time, every time.