Tantora Shrimp Series Micro Active contains live and active bacteria that break down aquarium waste. Micro Active is specially formulated to condition water for freshwater dwarf shrimp. Micro Active also contains probiotics that help with shrimp digestion and growth rate. Micro Active is highly concentrated--only 1 mL is required per 50 liters (13 gallons). Roughly, that's 1 drop per 1-2 gallon. 60ml bottle.