In addition to plant supplementation, the substrate for the aquarium serves the purpose of purifying the water, stabilizing its pH due to the presence of calcium carbonate. Sand rich in marine bacteria effectively removes nitrates, nitrites, and ammonia, thereby restoring the natural balance of the tank. Before purchasing plants, it is worth ensuring which aquarium substrate will best support their growth. A good idea is to combine the substrate (gravel + sand) and choose the appropriate grain size of the sand. Most often, for freshwater aquariums, the recommended grain size is between 0.2 and 0.6 mm - fine sand without sharp edges does not irritate the fish, which often search for food at the bottom of the aquarium. Such activity can pose a threat to the delicate roots of plants, which is why it is important to pay attention to whether the given aquarium substrate provides them with good adhesion, without which the plants will not have the opportunity to develop, becoming brittle and weakened. The choice of quality substrate for the aquarium affects the condition of the entire tank, which is why it is so important to choose a substrate sourced from distant corners of our world, namely places where the species of fish and plants that inhabit our aquarium naturally live and thrive.