They go out of date. You cannot ask them questions. Very often they have not been peer-reviewed so could be complete rubbish. Just because a publisher has agreed to print something, doesn't make it right. At least if someone says something stupid on here there will be someone else to tell them so.What you guys got against a good book ?
I've found Takashi Amano's Natural Aquarium Complete Works 1985-2009 to be an almost endless source of inspiration and there is quite a bit of technical detail hidden in the text as well - Nature Aquarium: Complete Works 1985-2009: Amazon.co.uk: Takashi Amano, Masatoshi Abe, Tsuyoshi Oiwa, Eriko Sekine, Yuka Hachinohe, Yoshinori Watabe: Books . Oliver Knott's Aquascaping: Aquarienlandschaften gestalten is another inspiration, but it's printed in German - http://www.amazon.co.uk/Aquascaping-Aquarienlandschaften-gestalten-Oliver-Knott/dp/3833824115/ref=sr_1_1?ie=UTF8&qid=1381357264&sr=8-1&keywords=oliver knott. This journal is also very very cool, stylish & informative - Liquid | Nature Aquarium Magazine