The CO2Art Drop Checker Solution (4dKH) is a pre-mixed indicator solution designed to help you accurately monitor CO₂ levels in your planted aquarium. Used with a CO₂ drop checker, this 4dKH reference solution changes colour depending on the CO₂ concentration in your tank. When used correctly, green indicates optimal CO₂ levels for plant growth, helping you avoid both underdosing and dangerous CO₂ spikes. The solution comes pre-mixed to the correct 4dKH concentration, eliminating the guesswork and ensuring more reliable readings than using aquarium water. A simple but essential tool for anyone running CO₂ injection in a planted aquarium. Features 4dKH pre-mixed solution for accurate CO₂ monitoring Designed for use with aquarium drop checkers Helps maintain safe and optimal CO₂ levels for planted tanks Colour indication shows CO₂ concentration at a glance 15ml bottle – long lasting with minimal usage per refill
