If you’re looking to add some natural beauty to your fish tank, lava rock is a great option. Lava rocks are porous and provide plenty of places for beneficial bacteria to flourish while they help maintain the pH balance of the water in your tank. Before adding lava rock to your tank, however, there are a few preparation steps you should take. First, rinse off any debris or dust from the rocks with warm water before placing them in the aquarium. Be sure that all visible dirt and grime has been removed before submerging them into your aquarium - this will prevent any dirt or chemicals getting into the water and causing harm to your fish. Next, soak them overnight in clean freshwater – this will help make sure no impurities remain on the surface of the rock which could potentially pollute or poison your aquatic environment. Finally place each piece carefully inside the tank so as not to disturb other decorations or plants already present – it’s important that you consider where you place these rocks as many types of fish like caves and crevices created by these stones! Following these simple steps will ensure that you have safe and healthy environment for both yourself and your beloved finned friends!