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 salt water 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