Dymax Calcite Sand is an ideal substrate for bottom dweller fish, corydoras and shrimps.
This is also a great substrate for a fish only aquarium, serving the purpose of providing a surface for the beneficial bacteria to build colonies. With todays filter technology, the size of the gravel does not really matter, but it is recommended to use a finer gravel if bottom feeders are home in the tank.
The substrate should be about 5-6.5cm in height (or depth) in the base of the tank (which is roughly 4kg of substrate for approximately 380 square centimeters of tank surface.
Please note: deeper layers especially with finer gravel sizes can pose a danger, given that food particles will sink into a less oxygenated area. This will over time produce hydrogen sulfite (rotten egg smell), which is highly toxic for the fish. ALL Sand should be carefully washed before use.