Thanks TOM for the response about DIY KITS. However, I would like to ask again about PMDD DOSSAGE. In the archives, it is recommended as 3 ml of PMDD per 100 liters of water and 1 ml PMDD to be added to every 10 liters of water replacement at the time of biweekly water change. Does this dossage hold true today? Dr Athale, Baroda, India.