Which substrate? Opinions, please

[DylanisHawttt]

Since you're looking for an economic choice, you could opt for 1.5" Miracle-Gro ($7.77 at my local Lowe's) and then cap it with 1.5" of Pool Filter Sand ($9/50lb bag) and there's your cheap substrate.

The only downside to using dirt is you can't move your plants around because they will root and pull up a lot of dirt and you have to do 50% WC for the first week-week and a half that you set it up.

[dmagerl]

Kitty litter also works well but you need to make sure it has no additives such as scent, clumping agents, deodorants, etc. But whatever you do, check it first to see that it doesnt dissolve in water. And of course, its beige. Not all people like beige substrate.

All the normal aquarium substrates you can buy, except for the "soil" substrates, have little to no nutrients, regardless of what their advertising says. Dosing ferts, whether in the water column or with root tabs, is usually required for healthy plants.

The main difference between a plant substrate and a non-plant substrate is its CEC, cation exchange capacity.

Gravel, sand, and other inert substrates have 0 CEC, and are rock hard.
High temperature fired clays such as Flourite, Eco Complete have higher CEC, and are rock hard.
Low temperature fired clays such as kitty litter, oil absorbers have higher still CEC, and are softer and may dissolve over time.
Soil type substrates such as Aquasoil, MiracleGro topsoil, are highest yet CEC with nutrients and tend to dissolve over time. (MiracleGro starts out as mud)