Battery bank weak after adding water to batteries

I would ask two questions. 1) what is the temperature of the batteries; the area where they're located and 2) what is the specific gravity of the cells?  Do you have a hydrometer and have you measured the specific gravity?  If so, what were the readings?

Specific gravity tells you much more than voltage or charge rates.

Urg, bad sentence...

"I have only checked the temperature by feel, and all I can say is that the ambient temperature of the box now is that it doesn't feels slightly cooler than the outside temperature."

I meant...

I have only checked the temperature by feel, and all I can say is that the ambient temperature of the box feels slightly cooler than the outside temperature (about 85F).

Sorry.

Have you ever notice how, sometimes, you can hear something said or read something written a certain way and it seems to turn a light on inside your mind? I think its called an epiphany.
Batteries were a big mystery to me at one time until I read in an old high school science text book that, "Batteries do not store electricity, they convert electric energy into a chemical energy and store that until such time as the electric energy is needed and, then it is convert back from chemical energy, with a cost."
Some folks think in terms of text, some in terms of math, I think in terms of images. When I read this about batteries, I could visualize, with my minds eye, what was going on inside the battery at the molecular level.
In the lead-acid battery, the active material within the positive electrode consists of lead dioxide, while the negative active material is a metallic lead. The positive active material is formed electrochemically from a cured plate, and influences the performance of the lead-acid battery. The electrolyte consists of a sulfuric acid solution, and as the battery discharges, the electrodes are converted into lead sulfate, which reverses when the battery is charged.
The basic principle behind "the battery" is two dissimilar metals and a catalyst. That was discovered by Luigi Galvani sometime in the 1700's while cutting a frog leg, Galvani's steel scalpel touched a brass hook that was holding the leg in place. The leg twitched. Further experiments confirmed this effect, and Galvani was convinced that he was seeing the effects of what he called animal electricity, the life force within the muscles of the frog. At the University of Pavia, Galvani's colleague Alessandro Volta was able to reproduce the results, but was skeptical of Galvani's explanation.
The Voltaic pile. A century and a half after Galileo's death, something of scientific importance was to develop in Italy. Volta, a former high school physics teacher, found that it was the presence of two dissimilar metals, not the frog leg, that was critical. In 1800, after extensive experimentation, he developed the voltaic pile. The original voltaic pile consisted of a pile of zinc and silver discs and between alternate discs, a piece of cardboard that had been soaked in saltwater. A wire connecting the bottom zinc disc to the top silver disc could produce repeated sparks. No frogs were injured in the production of a voltaic pile.

I realize this does not help you to fix your immediate problem. If anything it makes it worse because your here, using power to read my trivia. Actually, I think Mr. Owens has a good point in that regard. Lets us know how it all turns out, won't you?
 
F = k (q1 X q2) / d2  (Charles Coulomb)

I grew up hearing a phrase, "You've opened up a can of worms." As a child I imagined that worms came in a can and on those occasions that I went to the grocery store with my mother I would look for them on the shelves of canned goods. Of course I never saw them. Eventually though, on a summers fishing trip with my dad and a bucket of worms, I caught on to its meaning. A tangled mess. You can't tell where one worm ends and another starts.

Electricity is a simple matter to some and not so simple a matter to others. A never ending circle of events. For most, I believe that, as long as the light comes on when they flip the switch, thats all that matters.
I would explain electricity as, an amount of electrons over a period of time, but it can go a lot deeper than that. What is an electron? What is time?
What is an electron? For that we have to look at the atoms of matter or a mass.
So what are atoms made of? In the middle of each atom is a "nucleus." The nucleus contains two kinds of tiny particles, called protons and neutrons. Orbiting around the nucleus are even smaller particles called electrons. The 115 kinds of atoms are different from each other because they have different numbers of protons, neutrons and electrons.
http://www.chemicalelements.com/
Protons, neutrons and electrons are very different from each other. They have their own properties, or characteristics. One of these properties is called an electrical charge. Protons have what we call a "positive" (+) charge. Electrons have a "negative" (-) charge. Neutrons have no charge, they are neutral. The charge of one proton is equal in strength to the charge of one electron. When the number of protons in an atom equals the number of electrons, the atom itself has no overall charge, it is neutral. 
Some materials hold their electrons very tightly. Electrons do not move through them very well. These things are called insulators. Plastic, cloth, glass and dry air are good insulators. Other materials have some loosely held electrons, which move through them very easily. These are called conductors. Most metals are good conductors.
This is where the question, what is time, might occur.
We cannot conceive of motion without time. Clocks measure time. We cannot conceive of time without motion. When there is an imbalance of electrons between to atoms, the electrons will move (motion/time) from one to the other in order to balance out. We see this in nature as static electricity and on a larger scale lightning.
 A coulomb of negative charge is that of 6,280,000,000,000,000,000 electrons.
One ampere flowing for one second of time passes a coulomb of electric charge. Charles Coulomb first described electric field strengths in the 1780's. He found that for point charges, the electrical force varies directly with the product of the charges. In other words, the greater the charges, the stronger the field. And the field varies inversely with the square of the distance between the charges. This means that the greater the distance, the weaker the force becomes. This can be written as the formula: F = k (q1 X q2) / d2
Where F is the force, q1 and q2 are the charges, and d is the distance between the charges. k is the proportionality constant, and depends on the material separating the charges.

One could expand on all of this and theorize that, energy is equal to mass but only at a certain speed, the speed of light squared: E=mc2.
It can be construed that energy and mass, mass and energy are one in the same.

"The human mind is not capable of grasping the Universe. We are like a little child entering a huge library. The walls are covered to the ceilings with books in many different tongues. The child knows that someone must have written these books. It does not know who or how. It does not understand the languages in which they are written. But the child notes a definite plan in the arrangement of the books---a mysterious order which it does not comprehend, but only dimly suspects." ~ Albert Einstein ~