Our Palomino has 3 20# and I just alternate using 2 of them and when I have to turn on the 3rd one I refill the other 2. I like my tank set up and they last a good amount of time. On one tank used the fridge on propane while travelling 16 hours and then used the same tank to cook with for 5 days and still wasn't empty. I'm sure if running the central heat it would burn a 20# tank up quickly in 2 days. 20# tanks hold 5 gallons and 30# tanks hold 7.5 gallons so having 2 30# tanks is equivalent of 3 20# tanks.
2014 Palomino Columbus 3650TH
435AH 12V VMax Charge Tanks, 520 watt Monocrystilline Solar Array, Morningstar MPPT TS-60 CC,Morningstar Remote,Cotek True Sine Wave Inverter,Cotek Remote Controller,50amp Progressive Hardwire Surge Protector
2015 Dodge 3500 6.7L 4X4
2011 CanAm Commander XT 1000