My 150 litre tank has become super stable and is low maintenance low tech low stress which suits me, I would like to upgrade to something twice the size at some point. While I am attracted to doing a couple of low tech smaller tanks (30 cm cube and smaller, I already own) I'm wondering whether it's really worth my time and effort. Is there some ultimate limiting factor of eco stabiity for smaller water volumes in relatively tiny tanks, or have people here successfully maintained nano tanks over longer periods which only require water changes?