Two bags of Flourite would give you almost 3" deep bed with no added gravel.
You have to be very careful when mixing substrates. If the standard aquarium gravel you have is too large (and most of it is) then you will end up with the gravel on top and the other substrate on the bottom.
You have to be very careful when mixing substrates. If the standard aquarium gravel you have is too large (and most of it is) then you will end up with the gravel on top and the other substrate on the bottom.