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Homemade Aquarium Rock Backgrounds

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Many aquarists like to add realistic-looking backgrounds to their tank. Usually, these backgrounds resemble a wall of rocks and stones. Rock backgrounds not only look great, but they may confer subtle benefits on the tank’s inhabitants as well. While some hobbyists are better suited to purchasing a commercially made background, those with the desire and skills to build their own will enjoy the creative process, and visually pleasing results.

Benefits of Backgrounds

The primary benefit of rock backgrounds is their aesthetic appeal. While backgrounds are not necessary for the well-being of your fish, they provide visual barriers and well as habitat complexity, which may make your fish feel more comfortable. Additionally, backgrounds can serve to hide or camouflage heaters, filters and other devices as well.

Custom Vs. Commercial

Homemade products offer more design flexibility than do mass produced products. This is important especially for rock backgrounds, as you want the background to match your specific tank, and not look like every other one you see. Sometimes, commercial models will not fit in the tank as precisely as you would like. If you do not make adjustment, usually by cutting away excess material from the background, gaps may form between the background and the glass. Such cavities will tend to collect debris. Over time, as the material breaks down, it can affect the tank’s water chemistry adversely.

Materials for Manufacture

Commercial manufacturers typically guard their ingredient lists closely, considering it proprietary information. By contrast, hobbyists and DIY aquarists often share their experiences, though they may not have carried out rigorous testing to ensure it is safe. Most methods use a carved piece of plastic foam as a base, on top of which, various cements, grouts, rocks and resins are placed to give the piece realism. Regardless of the materials chosen, they must not leach chemicals into the water or disrupt the tank’s chemistry. Always ensure that any material you use is aquarium- and fish-safe. If you are in doubt, contact the product’s manufacturer or ask your veterinarian. Sterilize any rocks or stones collected from outside before using them in your aquarium by boiling them for at least one hour.

Creative Concepts

Do not limit your background design to rocks – rarely are underwater cliffs uniform walls of rock. Often, such walls in the real world include pieces of wood and aquatic plants as well; try to recreate this with your wall. While artificial plants are much easier to incorporate and maintain than live plants, you can carve openings large enough to accept potted plants. This way, if a plant fails to thrive, you can easily trade it out for a new one. Many hobbyists incorporate structures, such as tunnels, small caves or overhangs into their backgrounds, which gives the tank’s décor more depth – just be sure that they are secure, and will not collapse and injure your fish.