Waterpik WP-660 Aquarius Water Flosser

I purchase this Waterpik on 7-11-2022 and immediately loved the way it cleaned my teeth and mouth. It is a great addition to everyone's dental health. I loved it! I cleaned the entire delivery system often with hydrogen peroxide or vinegar and used Listerine daily while brushing at least twice. And sometimes I let the wand empty by lowering it below the counter so all the water could drain out onto a towel on the floor. I was pretty confident I was safe from mold or bacteria.However, about a week ago I noticed an occasional small black speck falling out from the wand as I was using the Waterpik. The second time this happened, I stopped using it and I've spent the last 3 days cleaning out the wand. What I found was disgusting and frightening.The tubing is easy to clean, but the rest of the Waterpik is open to water, mold, mites and debris which isn't noticeable until it starts to fall out while the water is spraying out of the tubing.I started exploring the wand and found it is not a sealed unit. Dirt, debris from mouth, bacteria or viruses can enter the wand and collect, finally turning to black mold within the wand. It is not in the stream of water from the white tube. It washes out as water rushes past the wand from your mouth or hand. I immediately started looking for the source of the black sludge and found that there was no way I could just dig it out, it would have to be forced out. So I first used a combo of vinegar and baking soda because that mixture bubbles up and forces dirt out of an area. Similar to what happens when a sink is slow running or stopped up and you treat it with vinegar and baking soda.I soaked the wand in this combination for quite a while. At first gently, but with more force as I saw the extent of the problem. I held the wand upside down over the sink and shook it and watched a disgusting mix of black mold and stuff literally pouring into the sink in small and large black chunks and what looked like tiny bugs. I tapped the wand against the side of the sink, using a towel so as not to break the wand. I tried to manipulate the wand to expose the cracks that hold it together and saw some dirt coming from the cracks and the two switches on the wand. It was pretty disgusting. I spent about two hours that day rinsing with vinegar and soda and tapping the wand upside down over the sink. But I knew it was not clean; I could not get a clean wash from that wand.I ran vinegar and hydrogen peroxide from the machine through the white tubing. It seems clean enough.But the white tubing enters the wand with a fairly wide space around it for anything to get in. That's where most of the mold/debris was coming from. That's why tapping the wand upside down over the sink was so effective.I knew it needed more work, so the next day I started over again after soaking the wand in hydrogen peroxide overnight. More black/brown sludge came out while shaking the wand both upside down against the side of the sink and the normal way. It was much better after more hours of cleaning like this, but I wasn't sure it was safe to use.So I soaked the wand again overnight and yesterday got to a point where I rarely saw any debris. It is not completely clean, but I may use it today after another cleaning.I am going to contact the Waterpik company and explain what can be happening to this model. I suspect the other models have a similar problem that nobody knows about. This could be dangerous, and perhaps a warning on the box or instructions should be prominently displayed. I'm not sure what the solution is, considering the way these are constructed. Fortunately, it is fairly easy to keep the white tubing clean.This is an expensive Waterpik model. I paid $79.97 in July for it, and see it is on sale today for $68.87. I'm not sure I want a new one. But at least I want to be reimbursed for my original purchase price because I'm afraid to use mine. I do have the original packaging that it came in, but I hope Waterpik doesn't want it back! It would be a waste of time and money to return it to them. I'll just have to see what they can offer. I do have a portable inexpensive back-up model which I can use, but it is not as good as the older one. And I see there is a potential for water to collect and remain inside the body of the portable one, too.I hope this inspires every owner to take a good look at their Waterpiks. It is a safety issue. I don't know the answer, I just know what is not working right for the consumer's health.BTW, I'm almost 84 years old, and I don't want to spend the rest of my life cleaning out Waterpiks! Not fun! And way too expensive :)