I use a Hozon brand mixer. I'm on my second one in 15 years. Once the rubber parts inside wear out it's just easier to buy a new one. --Jerry Lehmann, Kansas, USA <<I am a fan of the Dosatron, although it is not really suited to small scale home use (small potted collections). It is an ingenious mechanism and trouble free for many hours before it needs servicing in my experience. If you have used a Siphonex prior to you will wonder how you ever got along without it. You can get fixed or adjustable injection rates. The unit needs to be mounted on a bench or cart and this is a custom job. I'm told that Chemilizer is also quite good but is only available in a fixed injection rate. Dylan>>