I did the whole automated rain water thing for a year before I had to rip it all out because of moving to temporary house. I did learn that the best spray heads were the ones that send out 8 streams water in a circular direction and each head can be adjusted for optimal flow. On 15 gallon pots and smaller 1 spray head was plenty but needed to be adjusted depending on how big the pot was. On my big 30 gallon pots I used 3 spray heads and dialed them back to achieve the desired wetting pattern. I got a 2.5 hp pump to run it and it did fine for 10 plants at a time. My timer was set up on 3 zones, 10 plants at a time. I had to run the discharge pressure at 40-50 psi to get enough flow to the plants. To achieve the desired pressure I had to install circulation line with a valve coming of the discharge back to the rain tank and adjust the valve position to get 40-50 psi going to the plants. After toying with it a while and getting all the spray heads adjusted properly it was very nice!!!!!!!! I will never go back to hand watering again once our new house is built and every things automated again. One suggestion is to have a manifold with a 200 micron screen/filter for every zone. I had to clean the screens once every couple months with a tooth brush. I hand watered 50 something plants every day for several years and I'm here to tell you that automation is the way to go!!! I will never look back. Stay away from drip. Rain water is too dirty and you will have nothing but problems with drip. 1/2 inch Polly tube and the little 1/8 hose to a spray head that adjusts flow on a stick is the only way to go. The spray heads need to be the ones that send 8 individual streams. I can't stress that enough as all the other fan heads and bubbler heads clog up all the time.

Either the Dosmatic or the Dosatron will work quite well. I have had both, but prefer the Dosatron as the Dosmatic required repair, twice, and the charge was rather high. I have had the Dosatron about the same length of time and so far have not needed any repair. Mine is installed into the plumbing system, but if I had it to do again, I would put it on a mobile cart so I could use it in the greenhouse as well as for the outside plants in the summer.

Unfortunately in California we get absolutely no rain during the time of optimum plant growth. Thus, the efficiency of fertilization by manually applying fertilizer to the soil is actually quite limited when using a drip type watering system because only very localized portions of the soil are irrigated. Also the irrigation tends to be very localized at the surface, but then spreads outwards as it goes deeper. With this in mind, to fertilize efficiently you would have too precisely apply fertilizer to specific regions which correlate with the drip emitters and then to dig down relatively deep to achieve maximum coverage. I just don't have the time to do this. Also, clogging of the drip emitters is much more prevalent with solid dissolved fertilizers. I am doubtful that using a fertilizer such as Dyna-Gro in the relatively diluted concentrations that I hope to use (e.g. concentrations appropriate for constant fertilization) is going to have any significant clogging effects.

i have no experience personally with the ez flow product but i have read many reviews online that say it just doesn't work. as far as being expensive it is actually one of the cheapest available. seems like it would make more sense if you are feeding a lawn to use granular fertilizers applied to the lawn and then watered in. the injectors are used for drip irrigation mostly.