ProTec PC-2 Humidifier Tank Cleaning Cartridge, 2-Count Packages (1 pack of 2 cartridges)

These work really well keeping the tank from getting slimy. I think some poor reviews are because people think they are a substitute for cleaning the tank. You still need to clean the tank regularly! A small but necessary job . . .

These little doohickeys actually last a lot longer than the manufacturer states. We kept one in both of our humidifiers for years and never had any indication of mold or mildew. There are others that look like these things, but you need the ones that are made with silver. We only replaced ours because we replaced our humidifiers after more than a decade of use. I can't say yours will last that long, nor can I recommend you never change them. I can say they work great.

Got these as I was finding goopy stuff in my humidifier water. These work perfectly - keeps the water (and the filter!) clean.

I’m using these with my Honeywell HCM-350 cool moisture humidifier. I just drop a cartridge in the 1 gallon water tank and replace once a month since I refill the tank once a day. The cleaning cartridges are expensive imo, but they do seem to be effective. That being said, I don’t feel good about throwing a plastic cartridge out once a month. This is just terrible for the environment. I don’t understand why ProTec can’t innovate and create a product that does not require the disposable plastic cartridge. I ran across a different product called Essick Air 1970-2 Humidifier, 2-Quart Bacteriostatic Treatment for around $22 here at Amazon. It’s a liquid thats added to each water tank refill. No throw-away plastic cartridges, and it’s much cheaper. Only caveat, you have to be precise in how much you add to each water tank refill, only 1/8 capful to each gallon of water. I read that adding more than the recommended dose of Essick Air 1970-2 bacteriostatic treatment to your humidifier tank can release excessive chemical residues into the air, potentially irritating eyes, skin, or respiratory systems. So, the ProTec cartridge is designed so that you can’t use too much product, it’s safer, just drop the cartridge in, set it and forget it for a month. The Essick Air treatment requires careful measurement of product before adding to your water tank, but no plastic cartridge to throw away every month. If it accomplishes the same objective, I might give the Essick Air a try when I finish my last ProTec cartridge.

These are easy to use and I would have to believe they do what they are supposed to do.

This ball keeps my humidifier water clear and free of nasty bacteria.

I have purchased these several times in the past. I personally don't think any of these work 100% but this brand has never given me any issues.

My humidifier is structured so that the fan housing unit floats on water and the cleaning cartridge interferes with its flotation. I’ve had it in the humidifier for one month and so far the water is clean without older and no signs of mold or contamination.