Hollow limestone S

Limestone is used to decorate rock aquariums , particularly in habitats containing Tanganyika and Malawi cichlids. They can create beautiful rock compositions, often resembling a reef and a marine aquarium, hence the great popularity of limestone. It is also used as a base for live rock in marine aquariums.
It is also an excellent hiding place and offers the fish protection in the form of shade.

It increases water hardness and pH.