You can create aquarium decorations to design your own kingdom with any theme you desire. For example, in a terrestrial aquarium, you can make decorations which turn it into an outer space terrain, such as the moon or another planet, or you can make decorations that recreate a natural environment for your fish. Another theme for your aquatic aquarium might be the lost city of Atlantis. Use your imagination. Look at other aquarium displays for ideas and themes, such as in pet stores.
Write down your decorating plans on paper. Draw how you want your decorations to appear in the aquarium. This process allows you to save money and time when you start creating decorations. Look at other aquarium displays for ideas and themes. Think about your favourite places on Earth, then use your decorations to make a replica of one of those locations in your aquarium.
Select river stones, rocks, and green slates for added colour and naturalness. You may find stones you like along the beach, or even in your own yard. When you choose rocks, make certain you do not use limestone. Lime raises the pH of your tank water, making the water more alkaline and unsuitable for fish. Test for lime by placing a drop or two of vinegar onto the rock. If it sizzles, the rock contains calcium carbonate, found in limestone. (See Reference 5)
Arrange your selected rocks into any shape by gluing the rocks together with an aquarium silicone sealant. Build steps or make natural-looking caverns with glue and rock. The silicone sealant works best with glass and rocks, but not so well with plastic items. (See Reference 2)
Arrange driftwood creatively in your aquarium to create natural-looking borders and caves for your aquarium inhabitants. Borders in your aquarium help reduce aggression among territorial fish. You can also use pieces of wood to make small logs or to build hiding places. Use pieces of driftwood to represent exposed tree roots along a river. (See Reference 2 and Reference 3)
Place clay or ceramic pottery as decorations in your aquarium. Add colour in your aquarium by painting the pottery, or any object, using oil-base paint or latex paint. Use paint types that are safe in your tank and allow paint to dry at least twice as long as recommended by the manufacturer.
Use plants as decorations in your aquarium. Plants not only look natural and add beauty, but add oxygen to the water and consume organic waste. Avoid using too many plants. Place taller plants in the back of the aquarium with low-growing plants in the foreground. Plants create a spectacular landscape as they merge and grow. Shorter plants create space for fish to swim. Combine colour hues with the plants you choose for contrast, such as Vallisneria plant with long, intense green leaves combined with Echinodorus plant with its light green foliage. ( See Reference 3)
Purchase river stones inexpensively at dollar stores, craft stores and home improvement stores for aquarium decorations. You can also find coloured stones and pebbles at these locations for added variety. Find clay pottery of all sizes at gardening stores.
Keep stones and rocks away from the sides of your aquarium. Rocks can scratch the acrylic and add more pressure to the aquarium sides. Clean and cure pieces of driftwood before you use them to decorate your aquarium. Scrub dirt and debris from the driftwood with a cleaned brush. Do not use cleansers or soap on the driftwood since these chemicals will poison the aquarium water. Cure driftwood by soaking your pieces in a large bucket for 1 to 2 weeks. This removes excess tannin acid from the wood, which darkens the water. Keep the wood submerged under water at all times, and change the water when you see it has darkened. (See Reference 4)