Jen - i have looked at SMS charcoal but the problem you addressed with it being light is the main reason I have decided against it, and I have heard its much lighter grey in color compared to Eco. This is going in a deep tank that I dont want to have to get into much so I want a heavier substrate - that and its kinda a peeve of mine when the dang plants cant stay rooted lol. But I am sure the stuff grows plants well.
Tom - ADA Aquasoil is probably my first choice since of all the talk on the forums, and especially now since it is the same or actually cheaper than Eco. But I still havent figured out how black it really is, like compared to Eco.
And also what is Aquasoils weight per volume? Anyone know?
This is kinda my 'dream tank' that i want to be getting the best stuff for so I dont mind spending a little extra money. Basically when it comes to substrate here are the few things I am concerned with... how well it grows plants(nutrient properties, etc.), how well it holds them down, how well it will hold its shaped when scaped (like making mounds or ramping up towards the back), and how it looks visually (color).