Brightwell Aquatics Black Water Conditioner for Fresh Water Aquaria. Provides Humic Substances for all Planted & Blackwater Biotope Aquaria Overview * Establishes similar water conditions to those found in blackwater rivers, many of which are home to important aquarium fishes and plants. * May be used to help simulate the onset of the rainy season for encouragement of fish spawning. * Provides humic substances (humic and fulvic acid), complex bio-organic molecules known to increase the availability of important nutrients (such as iron, calcium, magnesium, molybdenum, copper, manganese, zinc, cobalt, and nickel) to plants, potentially enhancing the effectiveness of plant nutrient solutions in aquaria. * Formulated utilizing extensive research on aquatic plant nutrient requirements and riverine water chemistry.