Laterite

[Angry_Platy]

In the next few days/week I am going to be switching my sand substrate over to gravel/laterite with a substrate heater. My question is....how does the laterite, if mixed in the bottom 1/3 of gravel, help the plants who have their roots above this? Or is it simply that the laterite changes the composition of the entire depth of substrate?

I am just a little confuzzled....as usual

 

[jimbooo]

hi AP, basically the laterite holds the nutrients in the substrate, like a sponge. even though you are planting above this in a few days the roots will reach down to the tank base and set them selves in the laterite.

any help?