Flooded lead-acid opsie and how to correct best?

[ZYC tech]

OK, confession time and I need the wisdom from the list how to handle
this mess I created.

Last night I was in a hurry and wanted to quickly water my pack since
that was needed.

So, I grabbed the first of the 3 gallons that I keep for watering,
filled the auto-shutoff jug

and started going through my pack.

Two things happened, the first made a mess and the second is more
serious:

Because some battery boxes are between the frame rails, there are
cross-members that are above the filling caps of some batteries, making
access difficult

so they can only be filled with the jug at an angle.

Apparently having the jug at an angle can defeat the auto-shutoff
because the jug kept on burping slowly (I thought that this was because
it

was at an angle and not running as fast as with the other better
accessible cells) until I suddenly heard an agitated hissing

from the baking soda on the top of the battery, being eaten by the
overflowing acid from that cell. Oops.

I have put extra baking sode around that fill hole after closing it
carefully and I have since bought a plastic syringe with which I will
remove some fluid

from that cell and store it in a plastic bottle until enough water has
evaporated from that cell to put the acid back in without overflowing.

Anyone have a rule of thumb how much I should remove? until it is at the
same level as the other cells filled with the auto-shutoff jug?

The second issue is more disastrous and I can't still understand how I
got so confused:

after I used the 3 gallons to fill all batteries under the bed (the
remaining 6 under the hood had to wait till I bought more water)

I put the jug back at the shelf where I keep it.... and found the 3
gallons that I had purchased a couple months ago and stored there,

near the auto-shutoff jug. They had been behind some wood for a project,
so I had missed them earlier and I realized that I had used

*plain tap water* to fill my batteries, because that is what I had used
the old gallon jugs for - to store an emergency stash of drinking
water...

Quick calculation revealed that each cell received about 250ml of tap
water, because I could fill almost 3 golf cart batteries with each
filling

of the 2 liter jug. Of course that is just a few percent of the volume
of the cell, but I am wondering if the unwanted minerals in the
electrolyte

will cause premature damage to the cells (they are now 2 years old,
9,000 miles and I was hoping to go at least 1 or 2 more years with them,

getting 15 or 20k miles out...)

Do I need to have them emptied and refilled with clean acid or would the
dissolved minerals not matter much in the grande scheme of things?

I need to weigh my options and decide which route to go next & how much
cost and benefit each would have.

Your wisdom is appreciated!

[rks]

...wow...