I cannot thank you enough for the education you are giving me! I have adjusted all the zone settings so that the water duration and frequency makes much more sense to me. Not optimal because of my mixed type zones, but orders of magnitude better than a month with no water! I will keep adjusting not that I know how, thanks to you!
Thatās about all you can do. The two complicating factors for you are: So many zones, yet not really knowing the Nozzle Inches per Hour, and Different plants in the same zones. We can all make suggestions, but going ahead like that is definitely best. You have something that makes sense, and sounds reasonable. And you can simply fine-tune each zone, probably using the Crop Coefficient unless you canāt adjust it enough (max is 100%), depending on whether each zone seems over- or under-watered.
Good luck to you. And weāll still be here to help if you need it. 
Thank you so very much!
Thatās the best explanation Iāve heard of crop coefficient and allowed depletion! Thanks. In short, if all your other settings look right (which affect frequency and duration) then adjusting crop coefficient is what will get you more total water. Only nozzle rate will do that as well.
I honestly think that a dozen āadvancedā sliders that are in the end only used to adjust two parameters (duration and frequency) is a masterclass in over-egging the pudding.
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Correct. Crop Coefficient only changes the amount of water over time (without changing how much water is applied each day it waters). Nozzle rate changes both. Itās best, but also hardest, to accurately know nozzle rate.
Youāre right, the advanced sliders only really change two parameters. But by adjusting the advanced sliders, it gets you in the ballpark for those two parameters. Otherwise, youād have to just guess at minutes and frequency, and adjust from there, with nothing to start with. I do agree that after setting the advanced parameters as best you can, changes from then on would be better done with only two sliders: 1. More water at once. 2. More water per week.
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I use closed loop control. Water is put on lawn via sprinklers and rain. 5 moisture sensors report soil % saturation. I then apply common sense and adjust fixed schedule if needed. Trying to accomplish same open loop seems hopeless to me but many are doing successfully (I guess)
Hey Rraisley, your posts are super helpful in helping to decode what on earth the Rachio app is up to! I wondered if youād be willing to write a brief guide that lists out each variable in the Advanced Setting and what it does if you increase or decrease it? Also, a specific question, do you understand what the unit in/in means for Available Water? Is it inches of water per hour per inch of dripline? Cheers!
Thanks. While I was learning, I did write up this topic that might be of help to you:
A Beginners Guide on Understanding and Using ALL THOSE ***** NUMBERS!
Available water is the amount of water per unit that a given type of soil can hold. If Iād have invented the term, Iād have simply used Percent as the value (my soil, per a site that lists values based on actual location, is 17%). However, the Industry states it differently: They state the inches of water per inch of soil (yes, thatās the same as just a fraction); in this case my soil would be 0.17 in/in. And if youāre working with metric, to confuse things further, itās written as 0.17 cm/cm or 0.17 mm/mm. It could have been 0.17 miles/mile!
So, itās just a fraction/decimal/portion of the soil that is water, based on the soil type. That number times the root depth (D) gives a total inches of water that the top D inches of soil can hold, and if we want it to decrease by 50% before watering, it tells us we can apply AW x D x AD (Available Water x Root Depth x Allowed Depletion) at once, and then wait for it to use that much water before watering again. In my case thatās 0.17 x 6 x 0.50 = 0.51" of water. This calculated number is important because the amount of water applied by Rachio is calculated directly from it, and the length of time Rachio waits to water again is also calculated from it. Sandy soil canāt hold much water, so no sense in overwatering it, so you apply less, but more often.
Hope this helps.
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Hey Rraisley, that makes sense, thanks for clarifying that it is actually a dimensionless number!
I have another question about nozzle inches per hour. I have a long planting bed with a pipe running along the back, and a combination of dripper lines and dripper nozzles branching off it. How would you get to accurate nozzle inches per hour number?
Iāve not done that much with drip lines, except for my one, and Iām not sure itās right. But basically, there are two methods:
If, as you say, the area is narrow, and you end up watering the entire area (not just around each plant spaced far apart), then you can use the same Flow & Area system (GPM / Area x 96.25). Another method is to calculate how much water each plant needs, multiply by the number of plants to calculate how much water is required per week, then calculate the minutes needed to give that many gallons. A third method would be to use the first method, but estimate how much of the bed area youāre using for plants (say half of it), and modify time accordingly.
All of them, IMHO, require measuring the actual GPM flow, because it can vary TREMENDOUSLY, and that will directly affect the time you need to water. I still use Flex Daily for my drip zone, but it applies a lot of water at once, about once a week or less, due to root depth, and vary the Crop Coefficient if it gets too wet or too dry. Once dialed in, it should work well as the temperature changes.
OK, thanks. How would you go about measuring the actually GPM, other than putting buckets under all the dripper and drip lines?
While that sounds like a heck of a lot of fun, Iād simply read the number of gallons on the meter, run the zone for a while, read the gallons on the meter again, subtracting to find the gallons used, and divide the result by minutes. If the flow is /really/ low, you can time with a stopwatch the seconds for a gallon or whatever, but Iād start the other way.
Well, now I feel dumb for asking that question! Haha, very simple solution. Who wouldāve thought an irrigation system could be so confusing!? Cheers!
Wow. Rachioā¦I sure hope youāre paying Richard.
Richard, youāre awesome. I gave up on the flex daily. It was āfunā playing with it but not while I watched everything die. My original sense of it was correct. The algorithms, or the underlying measurements critical to them, do not work in Southern California. āCustomer serviceā is hesitant to acknowledge this, but in trying to trouble shoot, it became clear. I was inspired by all you helped me learn and converted most of my 11 zones to a drip system. It should save a lot of water and since weāre in for another drought, it will help. Thank you again, for all your time and patience.
Debbie
Nope. I just like helping where I can.
Thanks. Please tell my wife. 
Sorry it didnāt work for you. The only underlying calculations really involve the same factors (standard and Advanced) with Flex Daily that the other schedules use, but it appears more sensitive to being dialed in.
No problem. Definitely, drip zones will save water, although Iāve found them more difficult to determine exactly how much water is needed. Everything has its inherent advantages and problems, it seems.
There are a couple of estimates that are made via climate/weather data that do not work for this area. I decided I did not need to know the names of these variables or coefficients, just needed to get my plants watered!
Debbie
Iād be curious to know what those estimated are that you feel are wrong. What is it about SoCal that makes it not work?
Iām in Arizona, and once dialed in, my system runs without issue.
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