# Gravel v. Sand



## G.Minor (Sep 19, 2012)

I am on the verge of starting a planted tank using the Walstad Method. In your honest opinion, which works better gravel or sand?


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## Diana K (Dec 20, 2007)

As a cap, it is your choice. I would not go with too fine a sand (no play sand) nor too coarse a gravel. Anything from about 3/16" (fine gravel) on down to 30 mesh pool filter sand will work just fine. 

As the main substrate: Neither. One of the main points in the Walstad method is to use a substrate that contributes significantly to the fertilizer needs of the plants, both as an original supply, and with high cationic exchange capacity so that it actively holds and releases fertilizers for the plants. 
Sands and gravels do none of this. 
Mineralized Top Soil, Miracle Grow Organic Potting Soil and some other materials are quite good choices.


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## G.Minor (Sep 19, 2012)

Thanks Diana. I think I will go with gravel. I have already purchased the MG Organic Potting Mix.


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