Different AH 12v battery to battery bank OK?
No, you should generally only combine (connect in parallel) batteries that are identical, have the same age, are used in the same way or better: are new.

Also their voltages should be nearly the same, if not one battery will charge the other which can have severe consequences (too high currents flowing).

Batteries from different manufacturers, even if they have the same chemistry, should not be combined as it can result in unforeseen effects.