HS aqua Humalit Small is a multi-component nutrient medium for aquarium plants in small aquariums that get their nutrition from the soil. HS aqua Humalit Small contains, among other things, laterite from the natural habitat of the aquarium plants, a pH stabilizer so that the plants can absorb the nutrients optimally, porous material for the development of useful soil bacteria and humus substances for optimal transport of the nutrients to the roots.