I was a huge fan of this book, read it at least 4 times and preached the contents in another forum. I did a build thread. At the end of the thread I had switched over to high tech injected
It just didn't work for me. I found the reason was that I was trying plants that had a high carbon affinity. My plants withered until I was left with jungle val, the odd crypt and Anubis and tons of BBA.
Since joining this site I now would like to try vigorous surface agitation and water changes. Nutrients were not a problem in this tank. Carbon and perhaps oxygen were. It's no surprise the carbon chapter in her book is the weakest.
Low tech tanks definitely can be done but there's lots to consider.