Product review (4 stars): Better than the smaller, drop-in cartridges. Keeps humidifier cleaner for longer
I had been buying the smaller, pre-packaged drop in tablet sold by the same brand. I found that these worked well, but needed to be changed often in order to be effective. I bought this on a whim, though I was a little frightened by the extreme safety warnings on the bottle.

When the bottle arrived, I followed the instructions to a T- and only used a cap full of the product per gallon as directed on the bottle. I made sure not to spill any of it on my hands or skin. Since my humidifier has a huge reservoir, I only have to change it once per week. After a week of using this product, I was pleasantly surprised to see that the filters were still clean and there was no buildup of mold or slime.

The only downside of this product is that after pouring in the solution, there is a noticeable chemical smell to the mist coming out of the humidifier. After a few hours, I find that the smell dissipates. I find that if I run the humidifier a couple of hours before I'm going to bed, the chemical smell is gone and doesn't bother me. Otherwise, I think this product is good and much more cost effective than the drop in tablets I had previously used.