There are several options for the materials laid at the bottom of a koi fish tank, including pebbles, sand, and undergravel filters, etc. Each material has its own characteristics and applicability.
Pebbles: Pebbles are common items for the bottom. They can filter impurities and increase the stability of the fish tank. Choose pebbles that are smooth in shape, non-rusting, and don't affect the water quality, such as marble, jade, etc. Meanwhile, make sure that there are no sharp edges on the surface of the pebbles to avoid hurting the koi fish.
Sand: Sand can promote the circulation of water quality, filter impurities, and can also be used to bury plants, providing places for koi fish to rest and hide, thus increasing the living space and the amount of exercise for the koi fish. It's most appropriate to choose sand that is fine in grain size, natural in color, and doesn't affect the water quality.
Undergravel Filter: The undergravel filter is a more advanced item for the bottom. It can accelerate the water flow circulation, promote the circulation of water quality, and can also filter out organic substances and heavy metals, improving the quality of the water. However, the undergravel filter needs regular maintenance and cleaning; otherwise, it will cause harm to the koi fish.
Besides the choice of materials, the following points also need to be noted when laying them:
Environmentally Friendly and Healthy: Choose environmentally friendly and healthy items for the bottom. Don't use pebbles and sand that contain chemical substances such as preservatives and pigments.
Size and Texture: The size and texture of the items for the bottom should be suitable for the living habits of koi fish. Pebbles and sand should be smooth and without sharp edges, and the undergravel filter should meet the requirements of the size of the fish tank and the difficulty of maintenance.
Even Placement: The placement of the items for the bottom should be even and loose, and should not put pressure on the koi fish.
In addition, the following combination methods can also be considered when creating the aquarium landscape:
Combination of Aquatic Plants and Substrate Sand: Lay substrate sand at the bottom of the koi fish tank and plant aquatic plants in the substrate sand at the back half. This is suitable for those who appreciate the beauty of nature.
Combination of Aquatic Plants, Sand and Rocks: Lay uneven substrate sand at the bottom of the koi fish tank and place rocks and aquatic plants at the back half, so that the aquatic plants, substrate sand and rocks are organically integrated.
Combination of Various Stones: Pile up multiple kinds of stones, such as artificial rocks, lake rocks, pebbles, stalactites, corals, etc. into the shape of a cave, with fish swimming through it, forming a beautiful scene.
Stepped Landscaping Method: It's suitable for wall-mounted aquariums. The basic design is a stepped layout where the background aquatic plants gradually extend towards the foreground.