Whats this? A dosing pump for ants? Probably smallest peristaltic pump.

[Tavero]

Found this super tiny 8mm dosing pump on aliexpress a few weeks ago. It sparked my curiosity because its actually a true peristaltic pump driven by a bipolar stepper motor. So its the good stuff, instead of garbage DC peristaltic pumps that almost never work properly. Anyone has already played with them already? Or am i the first one.

After wasting two afternoons until i figured out that my Stepper.h library was misconfigured, its acutally now working and could be already used as dosing pump for a reef tank.

However I want to switch the arduino with a ESP to get wifi and web acess. That way it will be possible to change the dosing volume easily in a Smartphone browser.

Will this thing be actually useful? Meh... probably not. The dosing volume is only 0.5ml per minute. But hey it would be funny to use it on a Biota micro reef tank.

 

[Fish Fan]

I'm intrigued and following

I have a Raspberry Pi based Robo-Tank controller system setup, it controls very inexpensive, 12V peristaltic dosing pumps. I have calibrated these pumps through the Robo-Tank setup and they pump very accurately. These have a 3mm or 3.5mm hose that works well with typical 3mm RODI water lines, in my experience.

These are the 12V peristaltic pumps I used

I hope this helps; I'd like to follow your project!

 

[Tavero]

I'm intrigued and following

I have a Raspberry Pi based Robo-Tank controller system setup, it controls very inexpensive, 12V peristaltic dosing pumps. I have calibrated these pumps through the Robo-Tank setup and they pump very accurately. These have a 3mm or 3.5mm hose that works well with typical 3mm RODI water lines, in my experience.

These are the 12V peristaltic pumps I used

I hope this helps; I'd like to follow your project!

Good for you.
I personally was never happy with these pumps. First they were way too loud for my taste and second the dosing volume depends on the resistance of the silicone hose which is too variable for my taste. After the rotor of one oft these pumps got stuck and stopped dosing, i couldnt trust them anymore and wasted more time checking the dosed volume than i saved time by having the automation in the first place. In the end i stopped using dosing pumps alltogether until i switched them out.

I only trust stepper motors to actually turn as many times as I expect them to.

 

[Fish Fan]

Good for you.
I personally was never happy with these pumps. First they were way too loud for my taste and second the dosing volume depends on the resistance of the silicone hose which is too variable for my taste. After the rotor of one oft these pumps got stuck and stopped dosing, i couldnt trust them anymore and wasted more time checking the dosed volume than i saved time by having the automation in the first place. In the end i stopped using these pumps alltogether until i switched dosing out.

I only trust stepper motors to actually turn as many times as I expect them to.

I don't know of anyone who keeps reef tanks and uses 8mm stepper motors for dosing pumps. Simple 12V 3mm paristaltic pumps are the reliable way to go. The pumps I linked above can be calibrated, so they pump very, very accurately, in my experience.

Best of luck!

 

[Tavero]

I don't know of anyone who keeps reef tanks and uses stepper motors for dosing pumps. Paristaltic pumps are the reliable way to go (they keep human beings alive). The pumps I linked above can be calibrated, so they pump very, very accurately, in my experience.

Best of luck!

Peristaltic pumps can be driven by stepper motors or DC motors. Medical products use stepper motors as far as i know.
And yes you are right: there is probably no commercial reef product that uses stepper motors so most reefers dont use them. However there is only one reason DC motors are used instead.

 

[Fish Fan]

I wish you the best

 

[Tavero]

I did throw a simple Webserver together. Well chatgpt did. Hopfully i can insert the stepper control before the code implodes on itself.

 

[HappyFm]

I’ve used it — exactly the same pump you mentioned above. You should try it with ESPHome combined with Home Assistant. It’s actually quite easy (at least for me) to set up. I’m using them for my DIY DKH meter. Since the flow rate is quite low, the dosing is very precise (down to individual drops).


I’ve thought about using them for trace element dosing, but diluting the solution and using a higher-flow pump is actually much easier.


Conclusion: I’ll only use this pump for DIY automatic measurement projects, mainly to reduce the overall machine size.

 

[Tavero]

I’ve used it — exactly the same pump you mentioned above. You should try it with ESPHome combined with Home Assistant. It’s actually quite easy (at least for me) to set up. I’m using them for my DIY DKH meter. Since the flow rate is quite low, the dosing is very precise (down to individual drops).


I’ve thought about using them for trace element dosing, but diluting the solution and using a higher-flow pump is actually much easier.


Conclusion: I’ll only use this pump for DIY automatic measurement projects, mainly to reduce the overall machine size.

What driver did you use? Did you have issues with a hot motor? While Home Assistant seems like a convenient idea to control dosing pumps, it would habe bloated this project and made it dependent on more expensive hardware.

As of right now, i have already completed this project. Im just waiting for a shipping that contains additional tubing. Overall that pump did cost me less than 10 bucks and i will post the build and instructions when im done.

 

[HappyFm]

Of course, you can program it to run automatically without using Home Assistant — you just need to install ESPHome and set it up to operate as you like.
The motor gets hot because:

• If it gets hot continuously while running: you need to reduce the current flowing through it — specifically, lower the voltage just enough for it to operate properly. You can also improve its cooling with a small aluminum heat sink or a fan.
• If it gets hot after running: you need to turn off all electrical signals (in your code) once the operation is complete. I believe you’re keeping the final loop state active, which means current continues to flow through the motor even when it’s stopped — that’s why it overheats.

 

[Tavero]

Of course, you can program it to run automatically without using Home Assistant — you just need to install ESPHome and set it up to operate as you like.

Yeah maybe. However i dont feel comfortable to work myself through all that dokumentation right now. Just figuring out how the device builder works would probably take me longer than chatgpt took to write that code

The motor gets hot because

• If it gets hot continuously while running: you need to reduce the current flowing through it — specifically, lower the voltage just enough for it to operate properly. You can also improve its cooling with a small aluminum heat sink or a fan.

Like i said, i want to keep it as small and simple as possible (for me). I doubt there will be anyone else interested to rebuild that pump anway. As you wrote, the flow rate is extremely low.

Sure i could lower the voltage with a step down converter. However that would add an additional component. The stepper driver is a MX1508 for 70 cent. And that 8mm stepper motor is actually rated for 5V. Thats why i asked.
Meanwhile i have just reduced the PWM signal. Should be enough. I wont use it to dose for several minutes continuously anyway.

 

[Tavero]

And with this im done. No home assistant for now but whatever. Not like it would make the pump any more useful. Overall cost is around 6-8€ depending on the somewhat volatile aliexpress prices.

The casing is 3d printed. With a somewhat properly calibrated printer the cover snaps close permanently with a little push.
Even the hose connectors are 3d printed, but that part is so small, a resin printer is necessary.

To change the settings i have to connect with the dosing pump over wlan and enter the IP address 192.168.4.1 in a browser.

I actually like it better this way. No need for a dedicated app that may or may not be obsolete someday.

 

[Tavero]

Btw final size is 38mmx32mmx22mm without hosing. Building takes around 15-30 minutes.

I was thinking about throwing together a quick guide, however i have to check where to upload the files.

 

[Christian123]

Hello Tavero,

I am thinking of building a dosing system with an Arduino. I like the idea to change the settings via the smartphone/IP address.

I found also the 8mm stepper pump. Do you really use a MX1508? That is for DC pumps, not stepper. At least what I found.

What is the volume you can pump in one minute with these mini pumps?

I run as a beginner a 240 L freshwater tank. At the moment I use volumes between 3 to 7 mL for Fe and CO2 supplement. Later should come also NKP supplement and hopefully a CO2 system, that I don't keed the liquid CO2 supplement.
I run the tank also without a cover and try to think if I can use a normal DC pump with a sensor for automatic refill...

Do you think these small pumps can do the job for dosing supplements?

I would be happy if you can share more about your code and wiring. Do you use a raspberry?

 

[Tavero]

Hello Tavero,

I am thinking of building a dosing system with an Arduino. I like the idea to change the settings via the smartphone/IP address.

I found also the 8mm stepper pump. Do you really use a MX1508? That is for DC pumps, not stepper. At least what I found.

What is the volume you can pump in one minute with these mini pumps?

I run as a beginner a 240 L freshwater tank. At the moment I use volumes between 3 to 7 mL for Fe and CO2 supplement. Later should come also NKP supplement and hopefully a CO2 system, that I don't keed the liquid CO2 supplement.
I run the tank also without a cover and try to think if I can use a normal DC pump with a sensor for automatic refill...

Do you think these small pumps can do the job for dosing supplements?

I would be happy if you can share more about your code and wiring. Do you use a raspberry?

MX1508 is a hybrid stepper. It can drive DC and stepper motors. If you asked AI to find your information, it probably gave you a wrong answer. It did that for me too.
MX1508 is by far the cheapest stepper and even more important, is always sold without presoldered pins.

Volume is around 0.5ml/min. I use then for dosing po4+ and no3+ right now. I'm using other pumps with higher dosing speed for alkalinity, but volumes up to 10ml per day should be possible if the pump runs several times a day.

I personally don't like to run this pump for more than 30 seconds continuously. For one, it is getting quite hot after a while, while being stuck in a 3d printed case. But more importantly this pump is quite loud (for me). At least for a low power stepper dosing pump. Not as loud as a DC dosing pump mind you, these are ridiculous loud. However my tank is usually totally silent and inside my bed room. Soo...I guess its a non issue for other people that run a skimmer constantly anyway.

As I've mentioned I used a esp8266. Small, cheap, and with integrated Wi-Fi capability. They also are giving me far less driver and connection issues than traditional atmel modules.

I would have already released a guide already, however my code a total mess and a wall of text. Maybe its time to create a github account...
Also, setting up the software for flashing esp8266 isn't as straight forward as for the esp32 series. You need to import the libraries manually into arduino ide.

Wiring is as straight forward as it could ever get.

-Red and white of the 8mm stepper motor to motor A, brown and black to motor B. Polarity doesn't matter.
-IN1- IN4 pins of the stepper driver to D1 - D4 on the esp controller.
-5v and gnd pins on stepper driver to 5v and gnd on esp controller.

 

[Tavero]

 

[Christian123]

Thank you so much for answering my questions.

As I can see these mini stepper pumps are maybe too slow. I thought about pumping the supplements in smaller doses, but if I go for the 7 mL Carbo (liq CO2) I need 28 dosing steps, if I don't want to run the pumps more than 30 s.

Which DC pumps are you using for that rage of volume?

First I thought about getting a Chihiros dosing system, but I found my old Mega2560 that I used for a watering system for my plants on the balcony during holydays. Since I moved I don't need it anymore and somehow I want to do something usefull with it.

I mean with the arduino stuff you can also operate a display/e-paper display and a thermometer in addition to the dosing system. Or show also other things on the display. I guess I would check the display more often than calendar..

 

[GarrettDie4U]

Btw final size is 38mmx32mmx22mm without hosing. Building takes around 15-30 minutes.

I was thinking about throwing together a quick guide, however i have to check where to upload the files.

yes pls id like to see a guide !!! for everything and the chatgpt thing too pls

 

[Tavero]

Thank you so much for answering my questions.

As I can see these mini stepper pumps are maybe too slow. I thought about pumping the supplements in smaller doses, but if I go for the 7 mL Carbo (liq CO2) I need 28 dosing steps, if I don't want to run the pumps more than 30 s.

Which DC pumps are you using for that rage of volume?

First I thought about getting a Chihiros dosing system, but I found my old Mega2560 that I used for a watering system for my plants on the balcony during holydays. Since I moved I don't need it anymore and somehow I want to do something usefull with it.

I mean with the arduino stuff you can also operate a display/e-paper display and a thermometer in addition to the dosing system. Or show also other things on the display. I guess I would check the display more often than calendar..

I dont think doing 28 dosings per day is an issue. Running the pump longer than 30s technically isnt one either as long as the case is printed in something other than pla. Putting a heatsink on the motor is an option too. However the purging of even my 30cm tubing takes a long time, so this is one aspect that would annoy me after a few times.

I don't use DC dosing pumps. They are too loud for me. I use a DIY dosing pump built around a 28BYJ-48 stepper motor for larger volumes.

Sure you could use your mega2560 for this kind of project. I moved away from Atmel because the drivers were always giving me issues and were a pita to get working. ESP are often cheaper and have wifi, oled displays ect already build in.
But if you want to use your Atmel because it is laying around, sure.

yes pls id like to see a guide !!! for everything and the chatgpt thing too pls

I'll see what I can do. What do you mean with the chatgpt thing?

 

[Christian123]

Thank you for your answer.
I have the Mega2560 laying around, but I would need a wifi modul anyway. I don't want to reprogram the Mega always just to adjust the volumes. Then I could do everthing on the ESP directly.

Does the liquid run down the lines, that you need to fill then? I had this issue with cheap DC pumps in an other project. I would estimate the tubes from the pumps to the top of the tank will be about 100 cm.

But now other people told me, that I don't need to dump too much stuff into a freshwater tank. But ok, they don't sell the supplements.

I am still confused if I need the supplements or not. Maybe I need to go first for a good water testing kit. Now I have test strips, but they are not even in the range of the drop tests.