Chapin InternationalChapin HydroFeed 4702, 32 Ounce, No Color

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.

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.

2023 UPDATE: Even worse. It was emptied, dried, and stored inside during the winter. Filled, connected, turned on, and it spewed solution everywhere this year. Bought an "O" ring that did nothing to help. It continued to soak the side of my house with plant food so it's in the trash now. What an utter waste of money!Original review: This seems really well made and I was prepared to love it. I put half a Miracle Gro refill bag (crystals) in this to test its use rate since that amount in the hose-end feeder lasts about half an hour.I have now run the sprinkler attached to this for 19 hours over two weeks. There has been absolutely no change in the cartridge - it is still full of dark blue liquid. If it draws anything at all, it is not possible to measure. I am returning it as defective. Maybe some of these work but this one does not.UPDATE: after a tremendous amount of online digging and some experimentation, I found that it actually does sort-of work. The tricks are these: you must remove everything from inside the unit, even if you are using crystallized plant food. You must pre-dissolve the crystallized and pour it in. Then it does actually distribute it but it is still very, very, very slow distribution. You have to water basically all day to use up a third of it. The old 1990s miracle grow feeder that worked so well is a different proportion and I think this one is so tall and narrow that the water passing through it doesn't churn up the contents more than about a third of the way down the container.

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 .