Instant Ocean Hydrometer`s new improved design delivers precise full-range salinity and specific gravity readings - accurate to 0.001 - every time. Easy-fill convenience keeps hands dry when filling. It has a durable, permanent ne...
Hagen Living Sea Hydrometer with Thermometer—Small
Easy to read
Thermometer—C & F
Unique intergrated hydrometer and thermometer. Provides accurate measurement of specific gravity (degree of salinity) in a saltwater aquarium. Patented design enables device to be permanently installed inside aquarium, allowing ti...