Exactly 8 months later and I had to make up a new bottle of homemade cleaning solution. I used up the rest of the distilled water plus some filtered water from the fridge for the rest. I used 11 drops of sweet orange essential oil, only because it was the first bottle I found. I marked the spray bottle at the one cup & two cup mark so I won’t have to use the measuring cup next time. I don’t use a lot of cleaning solution because I use a micro fiber cloth and the micro fiber cloth works better when not overly saturated. This is what works for me.