Concentrated and efficient fertilizer for aquarium plants in fish tanks containing essential bioelements: K, Mg, Fe, Cu, Co, Zn, B, V, Mn, F, Se, Ni, Mo. Specifically suited for use in well-established aquariums with fish as it contains neither nitrates nor phosphates. Ideal for using in nano aquariums. Metal elements in the form of chelates present in the fertilizer are stable in water in a wide range of pH and hardness.