Deciding between crushed coral and aragonite or live sand can be difficult for many beginner hobbyists. There are only a few instances when crushed coral should be used over aragonite or live sand.
Saltwater Aquarium Crushed Coral
Crushed Coral is literally made from crushing up dead coral skeletons. The added benefit of using crushed coral is it provides a buffer against swings in pH, like aragonite and live sand. The major difference is crushed coral is heavier and larger than traditional aquarium sand, so it will not move around in high currents. It can also be better if you plan to keep large fish as they sometimes disturb the aquarium substrate.
Crushed Coral Review
There are a number of major disadvantages to crushed coral. You will need to siphon the substrate to remove any debris at least once per month. You will find that the substrate turns a brown or tan color. It is hard for sand sifting creatures to keep the sand stirred because the crushed coral is too large for them to effectively move around. In conclusion, most hobbyists should use live sand or aragonite as their substrate for a saltwater fish tank. I don’t recommend crushed coral for the majority of saltwater aquariums, other live sands can be purchased online.