What does filter gravel mean in practice?
Graded fractions support the finer medium, cover the distributor and distribute water evenly across the cross-section.
When does it matter?
Bedding that is too fine may get into the crevices of the basket, and if it is too thick, it allows the actual bed to move down.
Which solutions are related to it?
The granulation and height of the layers are selected according to the distributor and the bed, and the material is intensively rinsed before work.