This si for everyone as well as specific to the original poster:
Diana Walstad was amused with the DSM idea I suggested when we met in Australia. I also suggested a single species so no CO2 competition between species. She has an article about using HC in a non CO2 it here:
http://www.atlasbooks.com/marktplc/00388Shrimp.pdf
This dusko's page on it, a pretty good tech run down, you do not need to know all this, but........at least it is here
http://lowlightlowtechplanted.blogspot.com/
This will help on doing cheaper alternatives to ADA aqua soil.
Note: you CAN USE ADA AS successfully, very much so, with a non CO2 method/no Excel etc.
Likewise, you can use plain sand and ADA like scaping methods with non CO2(my example etc).
There are quite a few options, but somethings will cause some headaches, but experience sure helps.
So over time, you can modify things here or there to make such seemingly impossible rules that can be broken.
Still, it can be tougher for a newbie, and if they get frustrated and fail a lot, they quit.
I'd rather hook a few, and not lose any. The CO2 gas is always there if/when they are ready, likewise, getting off the dope, it is always there when you are ready to go non CO2.
Main argument is to get the newbie hooks and succeed with the plants.
Then they can do whatever.