Nutrient Rich Sandy Substrate

ADA powersand isn't sand, its pumice rocks the size of gravel mixed with ferts. Only to be used at the bottom level.

The other decorative sand offered by ADA is just sand with no nutrients in them.

Mixing something below sand will not work long term, eventually the sand will sink to the bottom.

The best way to have use sand in a planted tank is to separate the substrates into regions, plant substrate in the back and sand in the foreground where you aren't planting. Example:

http://www.mynatureaquariums.com/howto/howto.html
 
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