Cool, I was just looking at the ADA Aquasoil Amazonian and I'm thinking that is the way to go. Pretty expensive stuff. Any ideas how much I would need for this 20 tall? Also, do I need to be worrying about capping it with anything? I wouldn't mind going with some kind of black sand to help out the corys.
I made the switch and I am enjoying it! Since your substrate will be the major supplier of nutrients, your mentioned selection of ADA Aquasoil Amazonian will be a very wise choice (even though it is a bit pricy). If you take a look at the Extended Information tab it states the following:
ADA 60cm (24in. X 12in.) = U.S. 15 gal or Standard 20 Gallon (high or long):
- Regular 1- 9 liter bag
- Special type 1- 2 liter bag "S"
- Regular 1- 9 liter bag + or Special type 1- 3 liter bag ADA 90cm
(36in. X 18in.) = U.S. 58 gal.
- 2- 2 liter bags "M"
- Regular 3- 9 liter bags or Special type ADA 120cm
(48in. X 18in.) = U.S. 75 gal.
- 3- 2 liter bags "M"
- Regular or 4- 9 liter bags 1- 6 liter bag "M"
Special type ADA 180cm (72in. X 24in.) = U.S. 180 gal.
- 9- 2 liter bags "L"
- Regular or 9- 9 liter bags
- 1- 18 liter bag "L" Special type *note that a a 9 liter bag of is approximately 20 lbs.
I'd highly recommend the additional bag of whatever they suggest because, like stated before, a fertile substrate is key.