Yep, cheap old no name stuff works quite well.

I think mineralization via time/soaking, bacteria is the best method.

Think about fishless cycling, what do you think the 2-3 week time does for all the bacteria chomping at the NH4?

You kill everything with boiling/baking etc.
But it's faster, that's the trade off.

Given an option, the soak is good.

I'm not sure why Diana did not suggest these various methods, mine came from several folks who used soil, manures and my own nutty experiments with algae and NH4.

I know what ALGAE IS NOT INDUCED BY!
Using that, and then applying it to the various issues folks have with soil sediments, you really see a nice pattern.
I go after my most likely suspect, NH4.

This same pattern, if you account for higher lighting, CO2 etc starts to make good sense for the high light CO2 tanks as well.

Then you can see that the plants and algae grow and can tie all the methods and everything in between together.

What changes is the rate.

I think most that can and have mastered CO2 can master a non CO2 and really enjoy it.

They have at least three methods to try or consider, soil or water column or both.
And the same is true for CO2 enriched systems as well.
See if you can do all six with and without CO2.

Otherwise, try one of each, I think you'll enjoy it a lot.

Regards,
Tom Barr