Battery Numbers ?

[JCJC]

Taking a bit of time to discharge and equalise our batteries, question is I am putting 4.5Amps into them, they are taking an approx 50 min to charge (mixture of 3300's 3700's & 4200's), is there a way of working out AmpHour's that the battery is recieving?
Or would I have to do a discharge at say 30Amp to to get any meaningfull numbers.

Is there a way of telling when a set is going "off" by looking at charging/discharging numbers.

Thanks Mick