Like i said i cant draw.. power to the tank lol.. mine was setup with automatic chargers 6 amp or 2 amp each. It works series parallel because there is 4 seperate chargers. the charger sees the battery as a 12 volt battery this way. I was able to run the pumps the same time as the chargers but sometimes they would clip. ( protection) so what i did was just hooked up some relays that would kill the power to the inverter when either pump was powered up. i just did this setup because i had the 4 chargers already.. someone who has a multi charger could benifit hookin it up the same way. Auto chargers will maintain tha batterys without over charging... the street chargers would be the way to go though for a new system. but check this i use the starting batterys insted of deep cycles.. more cca's more POWER LOL... trust me it is better than hookin it up to the alternator. this setup will instantly have the battery's beck up in just minutes! think about it if you hop the shit out of it, the chargers will start at 6 amps each battery (24 amps total) will charge them up very quickly , tapering off to a 2 amp charge to top off the battery's then standby LOL .. No secrets here it works!