API Saltwater Test Kit. An accurate and economical liquid test kit. Tests tap water and aquarium water for 4 key parameters that affect the health of marine fish: High Range pH Ammonia Nitrite Nitrate. Unique clear dome packaging is waterproof space-efficient and makes contents easy to see. Includes laminated computer-calibrated colour card 4 glass test tubes with snap-tight caps and easy-to-read instructions with information on how to correct unsafe water conditions. Liquid reagent bottles include child-resistant safety caps.