One more thing, I believe a good carbon pile load tester is a pretty good investment for someone who had lots of batteries. It will help you sort out the wheat from the chaff regarding what’s good and what needs to be replaced.
They're good for testing charged starting batteries, but won't help ideally with cycling batteries, which need cycled for a proper test.
You can also use them to detect a bad cell, but hydrometers are much safer. If one cell has 25-50 points variance, dont bother charging. It may kaboom if you do.
With a load tester, any cell that percolates rapidly and emits gas is toast as well, but be aware that gas is highly flammable.
