Maintaining good water quality is the key to successful fishkeeping. The API Saltwater Master Test Kit is a complete kit for testing saltwater aquariums to protect marine fish and invertebrates from unsafe water conditions. The Saltwater Master Test Kit tests 4 key saltwater parameters. The kit is highly accurate and economical, and includes 6 bottles of liquid test reagent, a computer calibrated, laminated color card,4 glass test tubes with snap-tight caps, holding tray, as well as complete, step-by-step instruction booklet, including information on how to correct unsafe water conditions.