in aquariums there are four types of fertilizer for aquarium plants. 1- solid fertilizers for use as a substrate haquoss amazon substrates which are usually spread on the bottom of the aquarium and then covered with decorative gravel. 2- single-use fertilizers haquoss amazon base that act both as a substrate and as a decorative gravel. 3- solid fertilizers in haquoss tablets d4 spheres and pyramid plus if they are introduced into the gravel near the roots of the plants in the absence of amazon base or substrate. 4- liquid fertilizers haquoss d3 if fertilizers are regularly administered in water and supplement the consumption by plants of nutrients taken from their aerial roots. indica- haquoss amazon base is a high quality moist fertilizer of type 2 produced according to Japanese zen philosophy. contains oligo-elements in addition to macro essential nutrients for plants that are slowly released into the water. its natural composition ensures a csc optimal cation exchange capacity to the plants and their roots a luxuriant growth of the leaves and prevents their yellowing and detachment also thanks to its porous and granulated structure keeps the bottom aired avoiding the formation of toxic rotting areas for the roots and for the fish. it does not reduce the temporary hardness kh and keeps the pH stable. use - 4 liters approximately every 1000 square centimeters of the bottom surface of the aquarium. the product is ready for use and does not release any dust or dissolve it over time.