Uhm, I don't know if this will help you, or not but!
I used to fret over my batteries. I never understood them really, until I was thumbing through a high school chemistry text book and came across the explanation of a flooded cell lead acid battery that stated; these batteries do not store electricity, they convert electrical energy into a chemical energy and store that until such time as electrical energy is needed and then its converted back into electricity. It even gave the chemical equation.
I don't even use a hydrometer on my own battery bank anymore. I calculated my electric power needs for a 24 hour day/night period and sized the battery bank just a little more than 5 time larger. Then I sized the PV array to replace, what is typically used in that 24 hour period, in just one sunny day.
Oh, I also have a Bogart TM2020 battery monitor mounted in the wall right by the front door just above the light switches. http://www.bogartengineering.com/
It reminds me to equalize each month. Equalizing is as simple as pushing a button on the Trace C60 charge controller. When its done it resets itself.
Of course there is still the chore of topping of the battery bank with distilled water before the equalizing charge but that gives me time to inspect them for any possible problems and it all takes me about 20 minutes, once a month.
It all worked on a set of Trojan T-105's I had. I got a little better than 7 years of service out of them before they started showing signs of age. Hoping to get 20 to 25 years or better from the lastest set of Surette 530's.
One of if not the greatest means of increased longevity of a deep cycle battery bank is, shallow cycling.