Things You'll Need
- Aquarium
- Rocks
Instructions
Buy aquarium-friendly rocks. Lava rock is an excellent, affordable choice with an attractive appearance. Do not collect rocks from outdoors, since these can contain an improper mineral balance and negatively affect water chemistry.
Sterilize rocks by soaking them in boiling water for several minutes. Allow the rocks to cool in a dry area away from sunlight. Wash your hands before handling the rocks to avoid contamination.
Place taller rocks toward the back of the aquarium, so that an onlooker's view of the tank is not obscured. Lay tall, rectangular rocks horizontally. Vertical rocks give an aquarium an unnatural, cemetery-like appearance.
Lay smaller rocks in small clusters near the foreground of the tank. Keep all rocks a few inches away from the tank walls to maintain good water circulation.
Arrange the rocks to create nooks, crannies and cave-like areas so that the fish and invertebrates have plenty of hiding-places and foraging grounds. Avoid partially burying the rocks in substrate, which can trap bacteria and sediment.