I really started digging on the pump stuff the last couple of weeks. My system will almost certainly stay with direct DC. 24V would be more efficient and most likely less expensive but I will stick with 12V as a worst case during development.
If I can't make the diaphragm pumps last long enough to be throw away (5 years or greater) Rotary Vane pumps are very possible with 12V or 24V direct pumping. This stuff is addicting!!!! To put it mildly, my wife is slightly concerned with the obsession.
