In the 'On substrates...' forum Art mentiones that he uses 3-4 inches of Akadama to top the rich organic layer (peat, DYI Power Sand, etc.).
The Fertiplant instructions suggest a cap of 2 inches.
Steve's article suggests 1 inch cap.
Vectrapoint suggest 2-1/2' (front) to 5 inches (back) - http://www.vectrapoint.com/main/manual/bms1.html
Does the thickness of the top substrate depend on the amount of organics in the lower layers?
Does the thickness really matter? Would it be correct to say that as long as the substrate doesn't become anaerobic we are fine?
Are we striving to maintain a substrate that is aerobic from surface to bottom or one that is a mix - aerobic in some areas (organics layer) and anaerobic in another (Iron rich clay bottom layer may be?)?
--Nikolay
The Fertiplant instructions suggest a cap of 2 inches.
Steve's article suggests 1 inch cap.
Vectrapoint suggest 2-1/2' (front) to 5 inches (back) - http://www.vectrapoint.com/main/manual/bms1.html
Does the thickness of the top substrate depend on the amount of organics in the lower layers?
Does the thickness really matter? Would it be correct to say that as long as the substrate doesn't become anaerobic we are fine?
Are we striving to maintain a substrate that is aerobic from surface to bottom or one that is a mix - aerobic in some areas (organics layer) and anaerobic in another (Iron rich clay bottom layer may be?)?
--Nikolay