Charging a Battery Bank

I reinstalled the 75A when I realized it would function as an adjustable which is all I wanted anyway. After the failed 2hr try as a 3 stage and then plugging in the WFCO to "shore" overnight with no SG change, I tried the 75A charger set fixed at 14.7 using the 1800w generator. For whatever reason the batts didn't even register it was there, which probably means I've got something screwed up....just dunno what. Using shore power I hooked the cabled charger set at 40a up and voltage jumped to 16.1v and the chargers amp meter claimed 20a....my clamp-on is busted. SOC went from 0% to 100% ish SOC in 2 hours. That's great but faster than what I hear is reasonable. Here's a pic of my wiring. Controller, Charger, Inverters have a foot or so of #4 to terminals and then 5' of 2/0 to the batteries.