I've since done away with bleach bottles all together, and now use pool shock to create my own bleach. 3.77 for a small bag of shock, and one teaspoon makes a gallon of strong bleach.
Bleach starts losing its potency as soon as it's bottled. a 6 month gallon of bleach will start losing 20% of its potency every year, until it's nuthin' but salt, and water.. BUT: Granular bleach, aka Pool Shock, aka calcium Hypochlorite, will stay in its crystallized form for a hell of a lot longer.
Here's what the EPA has to say about it:
You can use granular calcium hypochlorite to disinfect water.
Add and dissolve one heaping teaspoon of high-test granular calcium hypochlorite (approximately ¼ ounce) for each two gallons of water, or 5 milliliters (approximately 7 grams) per 7.5 liters of water. The mixture will produce a stock chlorine solution of approximately 500 milligrams per liter, since the calcium hypochlorite has available chlorine equal to 70 percent of its weight. To disinfect water, add the chlorine solution in the ratio of one part of chlorine solution to each 100 parts of water to be treated. This is roughly equal to adding 1 pint (16 ounces) of stock chlorine to each 12.5 gallons of water or (approximately ½ liter to 50 liters of water) to be disinfected. To remove any objectionable chlorine odor, aerate the disinfected water by pouring it back and forth from one clean container to another.
Since reading Ron Fontaine's article regarding this, I studied and researched, and it's all true. I've been doing this for about a year now, and the savings on bleach bottles alone is worth it.
A 1-pound bag of calcium hypochlorite in granular form will treat up to 10,000 gallons of drinking water.. something to think about.
Thought I'd pass this info along. :)