Much appreciated, my eyes glazed over here and there but a great read. I think it's worth the effort, sitting doesn't work anymore, I don't want to replace chemicals with chemicals and the filtres aren't cheap. Out of the tap 8.4 after RO 6.5 and drops to 5.5 after awhile (which I have read by absorbing CO2 from the air but it keeps right on going down to 4.2 4.1 but settles around there, is that like a saturation point for 40 litres ? seedlings are up but look so frail and vulnerable... I have had a world of trouble with seeds over last few years, multiple sources, must be me I just let them down, I'll start a thread, maybe somebody will catch something.