Okay!
Got it.
How’s the speed for refilling the control box with 1/4 inch tubing?
Also I’ll probably be using the half inch piping as the mains and drawing out the 1/4th inch pipe as laterals, so they should be equal in length, right?
I’ve found it simpler to fill my rezervoirs like halfway through then open the sluices…system seems to be better at keeping it topped up than start from zero.
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Good questions, good answers.
I’d suggest positioning the bulkheads on the individual pots at or below the lowest water level you want to maintain in the pots. This system will still work if the tubes to the pots are above the water level in your controller, but you are relying on a siphon effect which can be problematic.
It is best to keep all the plumbing (main line and the lines to the pots) downstream of the controller at or below the controller in this extremely low water pressure system.
Since you intend to expand the number of plants your system feeds, I’d also suggest that you use 1/2" pipe between the main reservoir and the controller so that the only 1/4" tubing is from mainline to the pots.
I’ve lost track of how many plants you eventually want your autofiller to service, but the limiting factor is the volume of water it can deliver. Here’s how I’d model it.
Assume that large vegging plants at the peak of their stretch and early flower need as much as a gallon per day in a typical octopot grow.
The flow rate to provide a gallon over 24 hours is 0.09 ounces per minute or about 5.4 ounces per hour. That is what needs to be delivered to each pot.
So at the maximum flow rate your main reservoir needs to deliver a gallon per day for each plant to the controller, onto the mainline and into the tubing for each individual plant.
I’ve lost track of how large you’d like to scale this system, but with a 50 gallon main reservoir supplying two dozen thirsty plants in late veg you’d need to refill your rez every other day.
Your 1/2" mainline would be plenty large enough to supply 24 gallons each day, and the individual 1/4" tubes can easily handle 5 - 6 ounces per hour to the plants.
I may be missing something, but I think those ideas should guide your design.
Hope this is helpful,
-Grouchy
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I am just wondering if there would be any backflow pressure from the individual pots to the mainline.
Yes, that is the design plan I have in mind.
Yes! I’ll probably tie it down with zip ties
Regarding the number of plants, I will be experimenting from 16 to 36 clones in a 4x4. I am not too worried about refilling the rez as it can be automated pretty easily!
Thanks a ton for your suggestions! I will be posting pics in this thread once I start experimenting 
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Another good question Kev,
I have seen backflow when I needed to change out an octopot reservoir due to a pH problem. I always have an extra octo reservoir handy for this purpose, so I just swapped out the pot with the bad water with a partially filled reservoir. The controller exit valve was turned off at the time and I noticed that all the other plants on the system were “helping” to fill the newly installed pot.
That showed that some backflow probably occurs whenever any plant is drinking a lot more than the others or a new/empty pot is added to the system.
Think of it this way, everything downstream from the controller, mainline, small tubing and the individual pots are all hydraulically connected and working in tandem to maintain the water level set by the controller. So, yeah, Backflow, but it won’t matter much in normal operations because everything happens really slowly and all the pots remain at nearly the same level all the time.
I’m really stoked that you are getting into this. You’re going to have a bunch of fun once you have a little model system to play with. Here’s a refresher from my first post on the simple “Toy system” I started with,
In the picture below, the little red container is pretending to be an Octopot. The white bin is the Controller and the grey tub on the left is a ten gallon reservoir.
When the Reservoir is full, and the two blue-handle valves below it are open, the Controller bin will fill until the floater check-valve rises up and shuts off the flow.
The water level is adjusted by the float valve and currently set for the height of water in a “Full” 1 gallon micro octopot container (about 3.5"). The magic trick here is that if the Controller is set on the same level (floor/table/rack, etc.) as the Octopot, this setup will maintain the same water level in the Control Unit and as many Octopots as are connected to it.
As the plant drinks and draws down the red octopot, water from the Controller will refill it. Once the water level in the Controller itself drops, the float valve will open and the reservoir will flow until everything below is back up to full up again. As long as the Reservoir has water, all the attached octopots will stay full.
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Should the size of the pot matter in an octopot grow style if salt nutes are fed in an inert medium like Coco?
I have seen huge trees being grown in commercial ops using a 6 inch rockwool cube.
The media in a hydroponic grow is to provide stability to the plant and hold on to nutrients.
Does the size of the wicking netpot matter? I guess a bigger size will accelerate the wicking.
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You’ve really put your finger on an octopot mystery there @kevinmalone. 
The original octopots have big reservoirs and big fabric bags and they grow really big plants.
The micro-octopots have small reservoirs and smaller fabric bags, and they also grow really big plants.
A few folks have experimented with really small pots and also had good results (@SaintAliasKnife!). So I think the best answer is that nobody knows!
One thing to consider is that a properly setup octopot develops two root systems, one in the reservoir and another that fills the fabric bag. The relationship between those two root systems and the optimal balance between them is not completely understood.
My own preference is a three gallon fabric pot that is sized such that the upper root system almost fills the bag with roots. That approximately balances the size of the two root balls and I’m just guessing that is close to optimal.
There are plenty of growers who have more experience than I do with octopot growing and I’d suggest that you put this question out there to tap into their knowledge. @syn, @Papalag, @firehead, @Jetdro, @Floyd, @Enjoi802, @SaintAliasKnife, just to name a few.
Here’s a good starting point for more octo info if you haven’t already bookmarked it:
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The small octo uses same size bags as the the large one . Only rez is different .
Chris wants 10 to 11 inch’s of media above the rez
Smalls are a pain as i am filling every day now in late flower .
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Thanks @GrouchyOldMan for pointing me in the right direction as always!
Regarding the 2 root systems, I think the slower refilling of the rez might offer more explosive growth because of air gap, that’s the only point I can infer right now, let’s see 
@Jetdro If refilling is automated, do you think the pot size/rez size/net cup size makes a difference?
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as long as you have 10 to 11 inchs of media above rez wont matter . WHOLE PREMISE is setting up DIFFERENT root zones .
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.
That applies to soil only?
Or an inert medium too?
Any rationale for the 10 inches?
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sets up different root zones , whole idea of the pot in first place . It IS designed properly .
only inert mix in the sleeves
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They do need to be filled every day
I will be building the auto fill sys soon just need to get out and buy parts and find the time to build
That should be easy being retired but damn things get hectic
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trying these with 8" tall 1gal bags on tonys gg4 autos this fall/winter, also first time using hydroton in the wick. it did occur to me that if they did work (probably just for autos or sog), it would be much easier and less intrusive to create an auto-fill system with them. the issue being if you stick a 3gal grow bag on top of there its going to block the holes around the edges that could be used for filling.
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I have to agree. I noticed similar.
I dont know enough to hypothesize with confidence but it might be a function of root mass + capillary action of ready available nutrients.
on the thread linked above, the plants in the 0.5 gallon pot were smaller than the last few plants in 1 and 2 gallon pots.
seems 2gall sleeve on an octopup = large plant. 1gall = manageable plant.
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I’m using the small wicking SIP and watering everyday, but it’s only a plant or two in flower at a time.
Currently I am using the tall 3 gallon fabric pots iin a plastic one to cut down on losing so much water, keep the air layer on the outside of the container and this way it slows down the medias contribution to the humidity in there.
I have been getting 5 to 8 oz a plant so far with Mother’s Milk. They took a half gallon a day.
No way I’d try that many plants watering by hand.
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I ran into that exact problem with my octopups and a 3 gal grow bag. I had to kind smoosh the side of the pot over to allow me access to my fill hole. I’d recommend measuring the actual pot when you get it and see how big of a diameter you can fill with a pot before you’re blocking your water hole and then buy a 3 gal that has the appropriate diameter.
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i like the sizing of ipower’s bags. the 3gals fit really nicely on the regular micros.
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Okay, let’s troubleshoot.
Pics would be nice & remember, the flow is very slow, especially once the level difference between controller and the pots get close. Have you given it enough time to equalize?
The water flows slowly, but it works because the plants drink slowly too.
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