PureGuardian Aquastick, Universal, Genuine Guardian Technologies Antimicrobial Humidifier Treatment, Ultrasonic & Evaporative, Fits All Brands, Reduces Odors, 2 Count (One Pack of Two), GGHS15

Six weeks and zero residue.

We are in Michigan, which has a whirlwind of humidity fun throughout the winter months. Depending on the year, we have a VERY dry house the entire season but other years, there's an ebb and flow with warmer than normal temps. This has made it challenging for us to maintain the four humidifiers that we typically bring out 3-4 months per year. If they are running nonstop, I've learned that the filters last longer but when humidity ebbs and flows, we get a faster accumulation of buildup and need to replace filters frequently. I've tried chemical additives, vinegar, and rinsing filters off to maximize life. It's super annoying and time-consuming and has been minimally effective. Last year I tried these on a whim and was delighted at how well they work. We had a mild winter that didn't require humidifiers to be constantly running and ALL of our filters remained clean for over a month. The typical pink/black/brown slimy and odorous filters that needed to be changed sometimes biweekly, we had a collection of slightly colored filters. This came at the end of our winter, so I pitched the filters but have high hopes for a much smoother experience going into another Michigan winter. I wish I had given these a chance before. I was a skeptic but no more as these have earned a coveted space in our Subscribe and Save lineup for annual home maintenance items.

I tell you I have not had any mold in my humidifier since I've been using one of these for the season. I used to have a problem with black mold in my humidifier cause we use a Woodstove one of these are season and I have had no black mold, kind of speaks for itself.

Works, but I could see pink slime bacteria starting after I didn't wash the humidifier as soon as I should have. Probably would have been worse without this, though, so I'll keep buying them.

Impossible to tell if they really work...but seem alright

We use these aqua sticks in our cool mist humidifiers that we have to run year round. They greatly reduce the time between having to clean the humidifiers. They eliminate the particles that start to collect and the inside of the tank does not turn yellow or brown. As described, they do last several months and while they may be a little more costly, they are worth every penny. You can easily tell when they are coming to the end of their life because the pellets inside the sticks will turn very dark. Saves a lot of cleaning time! And they will fit every table top humidifier, unlike some of the similar products that are advertised.

Actually works! My cool air humidifier used to get a film of slimy stuff on it, and the water would start to smell like pee. I would clean it with alcohol or vinegar or hydrogen peroxide, and evn put a bit of each in the water itself. Nothing seemed to prevent the slimy stuff from happening. I bought these blue sticks with pretty low expectations. I followed instructions and cleaned the whole thing in chlorine water first, including the part where you turn it upside down, to kill any slimy stuff (looks a bit brownish). I kept it with that chlorine water for a few hours in the bathroom (smelled). Then I rinsed it all and re-filled it with just water plus the blue stick. This was 3 weeks ago. I've refilled the humidifier several times since. The blue stick just rattles around inside when I refill it with water. No sign of the slimy stuff or pee water smell, which would normally show up by now. It works! Customer for life. :) UPDATE: One stick seems to last about 60 days before a small amount of gray film starts to form again.

This product is very good. I have the Pureguardian Ultrasonic Humidifier Model No. H965 which is cylindrical and a tank capacity of 1.0 gallon. I had a lot of trouble in the beginning about a year ago preventing mold. Spending hours constantly cleaning it. Trying just vinegar in the tank also didn't work before I found these antimicrobial aquasticks. I found right away that using just one for one-gallon tank doesn't work. You need to use both. But in addition you need to add 3 or 4 Tablespoons of distilled white vinegar or the mold still happens even with the two sticks. So put in both sticks and 3 to 4 Tablespoons of the vinegar each time you refill the tank daily with fresh water. When you empty the residue water, rinse out the bottom unit (which should be clean) and pour out the tank covering the hole with our hand so the sticks to do not fall out in your dirty sink!. Refill with clean cold water from the tap. This should last the 90 days they say for the sticks. Then do a full cleaning of your tank and base. Full cleaning for tank should be about 1/2 cup distilled white vinegar and several cups of water shaking the tank vigorously for 2 or 3 minutes to remove the residue. Then rinse several times the entire tank and refill with new sticks after 90 days. But remember: 2 sticks and 3 to 4 tablespoons of white vinegar. Hope this works for you.

This product is brilliant. It keeps my humidifier clean for a very long time. No odours and no issues with the product either. Very user friendly.

Produit sécuritaire et efficace.

Looks to be working as advertised. Some comments identified a white powder but I've not seen anything. I use distilled water in my humidifier and that seems to eliminate that problem.

I've been using them for a month.... Still have White dust ... and honestly how can this work if they stay on the water for like a few hours only ? as I have to refill the humidifier every so often.... So for the few hours it stays in the water .... does it actaully changes anything ?

Bought for my husbands humidifier. I am always looking for a good option for keeping the tank and rest of the machine as clean as possible. Helps make it easier to clean and of course the much larger bonus - safe and healthy! he uses his humidifier daily.