To charge the batteries perfectly, you'll need to know what the charger/s is/are doing and the SOC of the batteries. This is found by measuring voltage and current while the charger is powered, not by watching an indicator light. You should also measure the SG with a hydrometer.
The bubbling may have been consistent with the mfg. process used and some plate shedding of those remaining materials. Remember, you are dealing with a chemical reaction as well as electricity.
To get accurate answers to your charging questions, the SOC of the battery and the above information about the chargers' operation is needed. Now that the batteries have had time to rest and shed the excess skin effect voltage, what is the State Of Charge?
