Chapin 4702 HydroFeed 32-Ounce in-Line Auto-Mix Fertilizer Injector System, 32-Ounce, Drip Irrigation System (1 Feeder/Package)

My setup: I use these with a drip irrigation system in my garden, and smart valves installed after these units to turn on/off the flow. I have a backflow preventer installed upstream of each unit to make sure I don't get fertilizer contaminating the main water source. I use jacks 20-20-20 fertilizer dissolved in water, I have not tried putting solid fertilizer pellets in, which the instructions say should work. Comes with a short hose (about 1ft (30cm)) which is handy for connecting to a downstream valve or splitter. Basic thoughts: These units cause no issues with the drip system or the smart valves and are easy to fill up. I let the regular water flow through these all the time and just add fertilizer whenever I want to feed the garden. If you only use with fertilizer, downstream valves or irrigation systems might be affected by the fertilizer. With colored fertilizer its really easy to tell when the fertilizer is gone as you can see the color slowly fade as fresh water is mixed into the bowl. You need to be able to shut off water to the unit in order to add fertilizer, so its handy if the upstream valve is close to where you install the unit, but it won't hurt anything if you have to walk back and forth during the refilling to shut the water on/off. The unit has a plug on top, which screws out to let you refill without taking the bowl off. There is a dish in the black plastic top to help funnel the fertilizer down into the unit. I find that this is a really slow way to fill it up. The liquid tends to form an air seal over the hole, and you have to wait for it to bubble down and break the seal, which is pretty slow. I find it much easier to just take the whole bowl off, fill the bowl, and then put it back on the unit. These are quite tall, more than 1ft (30cm), so they might be difficult if you have a tight space where you want to use them. If so you might want to look a the options with smaller bowls, as those should be identical, with just shorter bowls. A full load of liquid fertilizer will be flushed out in two 15min drip watering sessions of 8 4ft/9ft (1.3mx3m) garden beds fed by 0.5gph 6in emitter drip line. I haven't kept close track, so it might go faster than that.

Very practical to use once properly installed

I gave the fertilizer injector a 3-star rating on easy to install and easy to use because the rubber gaskets do not work properly. I tried every combination that I can think of by putting the blue gasket on the top. And the black gasket was positioned under the basket. And when I use the fertilizer injector the gaskets failed and water was spraying from the device putting fertilizer all over my patio I switch the gaskets around multiple times they did not work at all the device leaks severely losing fertilizer products by spraying them out of the top of the fertilizer injector. I fixed the issue by using plumbers tape you must use enough plumbers tape just satisfy the Deep threads on the injector. I went around the threads four times. No more leaking. Product suggestion: include some plumbers tape with your fertilizer injectors. The tape works 100% your gaskets failed every time and anyway I tried.

Easy to install. One problem I’m having is I’m not putting a hi flow of water on my drip system so the siphon system on the fertilizer doesn’t extract fertilizer as fast as needed .

I purchased this as I wanted to automate how I was fertilizing my garden and wanted to do it on a consistent basis. I was a little hesitant as there are not a lot of reviews for the product and the ones that are there are mixed. I took a gamble and have been satisfied so far. The quality of the product is very nice, surprisingly very robust. I had to get some fittings from Home Depot to make it work with my drip line (the unit is setup to accept garden hoses and you will need to adapt the threads for drip line. I did not have any leaks at all. I saw the YouTube video of the one guy reviewing this unit who said it leaked all over the place and returned it. Either he did something wrong or it was defective because I did not have the same experience, not even a drop of water. I did however use new brass fittings (to adapt for drip line) and did not use any Teflon tape or pipe sealant. Just threaded the fittings on hand tight and no leaks. How the unit works is a bit confusing and I had to e-mail the company for clarification. I initially thought that my concentrated fertilizer would be pulled up by suction into the drip pipe and the reservoir would draw down over time as the fertilizer is used up. This would mean that the concentration of fertilizer stays constant. HOWEVER... that is not how this unit operates (much to my initial confusion). What happens is that water pressurizes and replenishes the reservoir meaning that over time fertilizer gets diluted to the point where there is nothing in it. What this means is that if you are using this connected to a garden hose and manually watering your plants by hand, your first plant will get the strongest concentration of fertilizer and your last plant will get less. How much dilution depends on how long you run. A small garden it might not dilute for several watering sessions while a larger garden might dilute after one or two sessions. This isn't really a problem if you understand what is happening and just make certain you change the order of plants you water randomly from session to session to ensure the fertilizer is equally spread over time. In my case though, I used this inline with a drip system on a timer and the dilution isn't a problem as all of the plants receive the same concentration of fertilizer since they are all watered together through the same line. Over time the fertilizer concentration is diluted by water but you don't necessarily want to be hitting the plants with high fertilizer content daily anyway. So what I do is I fill the fertilizer once a week and let it dilute over time and then refill. In this application, it works well and I can already see my garden beginning to thrive.