Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: what is the life time of this product? For how long can you use each stone? are those stones sold separately?
Document: Works perfectly every time. It's easy to use, comes with everything you need (air stones, tubes, replacement fuse), and the price is right. Been using it consistently for months without a single problem. Very well made. Highly recommended.
The first one I bought was great, lasted a long time. I've bought 2 since then and find that the Ozone doesn't stay strong after a short period. These should be made with the option of returning the Ozone plates to be recharged. It's a nice size and offers a lot of ways to use it.
I bought this to make ozonated water to drink. I have used it to ozonate a quart of water at a time, on the 5 minute setting. It does exactly what it is supposed to do.I am very satisfied with the quality, design, ease of use, etc. The only thing that aggravates me is not a defect in the product. It is the fact that OZONE FREEKIN STINKS! *shakin my head*. Who would've thunk it.
I bought  this product for health sake.I like the idea of sanitizing utensils, de pesticide fruits, take out antibiotic and other chemical out of meats.Since I bought ozonator I try to use it every time I have chance.The fruits last longer for a fact!! !The meats taste the same. But I know that after 15-20 minutes I azonated water its better for me and my children to consume.After all its easy to use. Its clamed to be good for you.
This Ozone Generator is just what we needed. We have the round diffuser stone placed 1 &#34; in front of an A/C outlet duct that blows continuously, with the unit program set to the longest time between generation time periods. It keeps the whole house smelling and feeling fresh. At some time in the future we will try the unit with water to see what effect it produces.
I have used it to purify drinking water as well after filtering. We haul our water and if it sits too long algae forms. This helps to purify it. I have used other methods, but this does a gallon at a time and no chemicals. Unlike the UV light wand that only does a quart at a time. When using the ozone water in hand laundry or washing fleeces, greasy items still need detergent but much less of it.
This product definitely serves the purpose. Lot's of mixed reviews I see, however, this product is able to ozonate jugs of water in 20 minutes as well as oil. Not only that, but I will set it on a bed-with the stone on the end of the tube, and set the timer so it comes on every hour for 20min.Then leave it in that room all day with the door shut. I do a different room every couple of days, and it smells so fresh.
The shipping was extraordinarily speedy. The unit is electronically controlled for a one time treatment of a variety of lengths of time, or cycling treatments. It comes with two separate tubes, and three aeration stones, two white (fine) spheres of porous material for water and air treatment, and a gray sphere for oil treatment. It is an attractive design, larger than I imagined. When I treated a glass of water it neutralized odors in the kitchen.
This Ozone generator works very well. It is easy to use and quite quick. I wish it came with more information about ozonated water such as how long it is good for.
If you use it right and don't expect it to do the same as $2,000 ozone generators, it does an excellent job. It is without a doubt a very good value. Considering I have been running this generator for 20 minutes every hour (followed by 40 mins rest) everyday for months now, it's pretty rugged for the price. Very good value.When ozonating oilive oil the stone gets clogged. Watch for that or don't use the stone (just the hose).
Answer: Ive been using mine solid everyday multiple times a day for about three months. I make water for friends and I do olive oil. The oil process is slow and the machine isn't the most powerful, so you really can only produce a small amount of oil in about 3 weeks. That's if you do it one hour a day and keep it in the fridge between running ozone through it... And very little oil at that, about an ounce to be able to produce the desired finished product. It does come with 3 stones. Two for water and one for oil. The stones seem well intacted still but about a month ago I bought a flat stone with a higher surface area and finer micron. More bubbles= more ozone. And use a single glass of water under setting 5 (20 minutes)  And use ice water, that's been filtered already for the best results.  Water can only absorb a certain amount of ozone and is only effective for about 20 minutes after you make it. So the machine will give you one glass an hour because it needs to be turned off for double the time you just ran it for before running it again..... Also... I've researched its best to drink the water a couple times a day for three days, and then take a few days off so your body can remove the pathogens your trying to. Also it's key to take vitamins in your days your not drinking the water because ozone will deplete your cells of some valuable things as well.  I found that vitamin c, d3,e, niacin, fish oil coconut oil, garlic, goldenseal, echaenatia,  and those types of supplements give your cells back what they need, help you to absorb them and also work as additional antitoxins. A one a day vitamin may be sufficient, I don't know, the above mentioned list is the recipe that I've come to so far as I learn more and more about how to do it properly. Also you don't want to eat or take supplement within two hours of drinking the water. For instance, vitamin c and ozone cancel eachother out if taken at the same time, but if you take vitamin c a few hours after drinking a glass it makes vitamin c go nuts and can wipe out a nasty cold or flu in literally one application... I've read plenty of people saying they drink up to five glasses a day everyday and take no supplements but I don't know about all that... but I would do a little research and consider several views before getting into it... And I'm not saying that everything I've just written is right, or most effective, but there is countless hours of research I've done to get that far and I'm sure I've much to learn. This Is a little more than you asked for, and if you are anything like I was,  being new to ozone, there's a lot more to it then just drinking a glass of water! But in a short answer, the machine works great for personal use and comes ready to go. Doesn't have the power your gonna want later if you stick with it, but it's a safe place to start. I've since ordered a larger multipurpose that's due any day and plan on given that one to a friend...  Also beware of .gov site, American cancer research sites, FDA site as they mislabel, dismiss ozone validity,  confuse, and make the whole ozone thing seem dangerous or inconclusive... There is no money in it for these institutions,  meaning the money is in the treatment not the cure and is why they won't recognize, inform, or offer ozone treatment. Trust blogs from people all over the world that are willing to share their experience.... It saved my life. Trust that. Word man, good luck