For my planted tank I am currently using:

1" peat moss ($12/bale)
1" play sand ($3/50 pound bag)
and
1" pro choice select (had to order from landscaping firm $8/50 pound bag) (could also use just aquarium gravel.)

I add one layer, wet that hayer, clean the tank and level the layer, Then add the next layer.

I have found that (especially with the peat moss) maintains kh and gh and the plants go crazy.

my .02

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fw leiden since 1979, fo salt since 1979, mixed reef 55g 2002-2009. Strong emphasis on the tank taking care of itself. Balanced with plant life, no water changes, tap water, no filters in FW. Only dosing calcium, alk, mag in marine reef tanks. http://www.aquariumforum.com/f15/my-...ods-26410.html
recent tanks (till 2009) 7 years- 10g FW leiden 7 yrs, 55g mixed reef 7, 2 yrs, 20g FW leiden, 10 g fw leiden , 29g mixed reef, current tank 55g leiden