Things You'll Need
- Aquarium rock
- Silicone-based aquarium adhesive
Instructions
Choose the correct adhesive for the job. Never use solvent-based glues in your aquarium because they are toxic to fish. Commercial aquarium adhesive is expensive, but you can be sure it poses no danger to your fish when used correctly.
Wash and dry the rocks. Porous rocks dry quickly on the outside but remain wet inside for longer, so ensure there is no moisture or dust on the surface before you apply the glue.
Apply aquarium adhesive to two rocks and press firmly together. Repeat until you have created a satisfactory grouping.
Leave the structure to dry, according to the manufacturer's guidelines. Some aquarium adhesives take up to 24 hours to cure and become waterproof; others are dry almost instantly.
Empty your aquarium and make sure the glass is completely dry in the spot you wish to attach the rock pile.
Apply adhesive to the base of the rocks and the aquarium glass. Press the two items together very carefully. Do not apply excessive pressure or the glass will break.
Allow the glue to dry and then rinse everything with clean water before refilling your aquarium with dechlorinated water.