How does water fertilization process takes place using sands,charcoal and small stones?

Question

PLS.. give me the answer....... using the sand, charcoal,small stones,,,.. which one is the 1st 2nd and da 3rd....

and plz. give me some explanations about this .... thank you!!!...

and also, if u can give me the diagram it will be much better..

GOD bless...tc!!

Answer 1

Do you mean water filtration?

The water passing over the stones will block the large items.

The water passing through the sand will trap smaller particles and the water passing through the charcoal will absorb organic molecules.