Maybe everyone else already knew this, but I recently learned that bleach goes bad. My daughter wanted help making a pattern on some clothing with bleach, so we put some bleach in a cup and she used a paintbrush to draw the pattern. And nothing happened. We repeated the process, and again, nothing at all.
I was quite dumbfounded, so I did some googling. It looks like everyone knew about this except for me; bleach degrades over time. It has a shelf life of only six months, and starts to degrade after that. Bleach won’t be worthless after six months, but it degrades by 20% per year after that. The bottle of bleach I was using was nearly six years old and was completely ineffective at that point. And if bleach is mixed with water, the solution is only good for about a week.
We bought a new bottle of bleach and it did the trick exactly like I expected. From now on, I’ll write the purchase date on any bottles of bleach I buy, and I’ll only use fresh bleach. It’s safe to dispose of up to five gallons of bleach by pouring it down a sink connected to a municipal waste system. Flush it down with water when you do it to help dilute it.
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