sera Aquarium Gravel Floredepot Substrate is a long-term gravel substrate with growth promoter for freshwater aquariums. sera Aquarium Gravel Floredepot Substrate contains essential nutrients and trace elements and should be used with new aquarium set-ups and larger rearrangements. During the first 4-6 weeks the substrate provides the plants with everything they need in order to form strong roots and lush green leaves.sera Aquarium Gravel Floredepot Substrate+ promotes the development of strong roots for healthy plant growth+ extends the settlement area for beneficial bacteria to support biological balance+ ideal for use under gravel or sand for a sustainable supply of nutrients+ balanced mixture for optimal plant growth and healthy development+ long-lasting effect - supplies plants with essential nutrients for several weeks+ bag contents are sufficient for a 60 cm aquarium