The derivation of the nutrient (P) and reaction number (R) in terms of water quality, which plays a crucial role in POND ANALYST's plant selection, is presented in detail in
»Schwimmteiche - Planen, anlegen, richtig bepflanzen« b > Claudia Schwarzer & Udo Schwarzer, published by Ulmer in 2008 (ISBN 978-3-8001-5345-9).