Dosing pumps - development discussion

Growroom Design
#21

At this point, I hit a road block as my system, from the viewpoint of full automation, is entirely dependent on 2 way valves that are servo or solenoid actuated, yet the market seems to be lacking the exact type of valve I seek, ie under $25, made of plastic, does not require 3PSI to function and will allow flow from either direction. Another concern is monitoring EC and PH. There are solutions to this, but all in all, I can see it costing around $300 to buy into and work with Arduino. That’s not a big deal if you only have to purchase a single set of probes and related circuitry, which steers right back to the need for that specific 2 way valve. Otherwise the user will need to spend $300 per reservoir, not to mention added pumps for each needed function.

All that said, I opted to keep the project on the back burner till I can resolve my valve concerns.

As to your steps, yes, they look fine on paper, but like everything in life, it will prove to be much easier said than done. Best of luck! Let me know if I can help in anyway. I’ll be happy to contribute or give ideas if wanted.

#22

How about these solenoids? 12v and 0 MPA.

#23

solenoid valves generally will only allow flow in one direction, but not the other. Plus also, they generally require 3 psi of fluid pressure to open. That particular water valve is only a 1/4" and most grows use 1/2" PVC or poly tubing. I spent well over a year looking for a solenoid/servo valve that is 1/2", does not require a certain threshold PSI, allows flow in either way like a ball valve and is plastic so not to ever pollute a reservoir with oxidized metals, but sadly the market does not yet have this. I bought a 3D printer and have been trying to design what I need, but so far am unable to print what I need that moves correctly and remains water tight. I’ve since expanded my grow and put this on the back burner for a few months.

1 Like
#24

Ah, I didnt realize you needed that much flow volume. Good luck!

#25

I don’t need volume. I only use 160 gph pumps. I just need the ability to move water through my lines in either direction, otherwise I would need a set of probes and circuits for each reservoir and a lot more one way valves which is just not practical.

#26

Is there a must to have all the flow dependent? Or is it possible to have independent flow for You? I would recommend separate standard water flow system from nutrients mixing system. And pump it into standard tank when it’s ready.

#27

Here is an image of my current setup. The blue circle is the RO tank. It pumps RO to either of the sites (yellow box). The red lines represent valves and are used to dictate which pump can flow liquid and to where. The reason to have optional directions of flow is because sometimes that pump is flowing to the plant, sometimes through the circuit to collect a PH and EC reading, the other side of that circuit to be corrected or dosed with nutrient or PH corrector, and at the end of the week, it all must flow out the main waste line. Right now, I’m using manual twist ball valves and poly tubing, but I don’t have my dosers in play, nor do I yet have the EC and PH probes and circuitry, but all the plumbing is ran. I miss the convenience of Dial-A-Dose, but not having it directly plumbed into the plumbing circuit introduces problems of air getting in the lines and salts quickly gunking up. Not having the ability to electrically actuate my valves has my project at a stand still. I’m currently printing a new better printer and hope any of my servo valve designs will produce a functional valve that I can attach a servo to. Until then, I twiddle my thumbs.

#28

Guys how far are the nutrient doser developments?

1 Like