I have one DS-15 but it doesn't work unless the water flow is high. The only thing that seems to work when your crop-side water use is less than a gallon per minute is a pump.

We have a pair of DI-16's. Truthfully, the variable settings are never touched - easier just to vary the strength of the injection solution. Do a great job but are a little pricey. If you watch evilbay you can sometimes pick a pretty good deal on used ones (that what we did).

Tom

i'm amazed at how many models there are. i found a D25F1 for $229. there's also another brand, Chemilizer that looks like it does the same thing for $10 less. the price range on the D25F1 is also amazing...as much as $375.

I have used doatron injectors but in the last 5 years have switched to a "Mix Rite" injector. They were developed in Israel, Have fewer moving parts and I have had no down time with them . I currently am using 6 of them. They are also less expensive than dostron.