The bottom sand suitable for guppy is black gold sand, Dutch sand, river sand and coral sand. Guppies have strong adaptability and low requirements for bottom sand. As long as they can be cleaned regularly, most bottom sand can be used. Coral sand, in particular, is very suitable for laying guppies.

Because coral sand can make the water quality weakly alkaline, it is more in line with the water quality requirements of guppy. Although they don't have high requirements for bottom sand, breeders should clean the bottom sand regularly to avoid bacteria or food residues hiding in it. If conditions permit, it is best to choose a filter with strong power, so as to keep the water clean.

It is best to cultivate guppy fish in bare tank, because the scenery can not provide great help to guppy fish except to enhance the ornamental value. Even if some bottom sand can keep the water quality weakly alkaline, it needs to be cleaned regularly to better maintain the water quality. Especially, bacteria and food residues are easy to hide in the bottom sand, which is difficult to clean without strong filtration. But guppies can't adapt to too much water flow, and if the water flow in the filter is too large, it will make them unable to rest better. Therefore, it is best not to put bottom sand as much as possible.