<https://forum.aquariumcoop.com/topic/2466-stt-seasoned-tank-time-formula-beginning-ideas/#comment-18395>
<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
<https://forum.aquariumcoop.com/topic/2466-stt-seasoned-tank-time-formula-beginning-ideas/>