reef-pi :: An opensource reef tank controller based on Raspberry Pi.

[Ranjib]

Would a ULN2300 do the same job? I have lot of these from another build? also if so would it be the same pin layout?

I am assuming you meant uln2003. If so, yes, it will work, and the pin out would be pretty much same. But uln2003 is a 7 channel darlington array, and the relay pack I am using (ADJ SRP8) is 8 channel. So, you may need multiple of these. If I recall correctly, its also bit low power. Thats all, but you can certainly use them, in fact one of my build is using them,

 

[Ranjib]

Hi Ranjib,
It should be possible to extend I/O ports via the MCP23017 (I2C) . Also the PCA9685 could be used as digital output according the documentation. I have been thinking about a modular electronic/mechanical concept and this is my (mechanical) idea so far:

I made these drawings for myself this morning, because it helps to get a better understanding of the whole concept and questions to be resolved (e.g. size of the modules, way of electrical/mechanical connections, power solutions, etc.)


the I2C bus should work like this (side view, below top view)

Depending on the number of modules required, the I2C bus can be extended and present idea is to have additional 5V and 12V on the 'rail'. I think we should have a small (for single I2C devices, or connection of the single wire DS18B20 sensors) and a larger for I2C controllers with many I/O ports.



Already made a PWM board design with 16 outputs on a 6*13 cm size board (started to learn KiCad :) ) which mechanically would look like this:

The red circles I added as not yet fix for myself. Present idea is to plug module from top on the I2C bus. This will make the total design a little higher but potentially also smaller (width) and think mechanically it's better due to the I/O connectors on the other side.

Unfortunately it's not showing the audio 2 connectors and a 7810 chip. I want to make some modifications to this design to fit the modular concept and most likely will change the I2C address solution.
I know that it contains an SMT component, but if you look at the upper left side of the design, maybe that can be replaced by the PCA9685 module, haven't checked that yet.
Have not designed the piggy back board yet, but basically is copy of part of the main controller

I have some idea's about the overall housing (base with I2C PCBA) which then also connect mechanically to the individual modules (didn't made a drawing of that yet)

I'm waiting for some electronic components to arrive (they are very expensive in Europe and Asia takes time :-( ). I'm also planning to design a MCP23017 module. Any comments/critics are welcome, it can only help me/us to come up with a flexible electronics/housing design.

Right, but we need additional code and configuration to support this in the software side. I have thought about doing this, but as of now we have seen very few cases where users are limited by the 22 gpio pins

 

[Ranjib]

Could the pi zero be used as a standalone relay controller, taking care of switching and timing of 8 sockets?

Yes

 

[Ranjib]

Yes

In fact reef-pi is modular by design. You can use any single module to roll up a monitor/controller with only one specific feature

 

[Ranjib]

Hey all, especially Ranjib.

I am from South Africa and have recently stumbled apon this project. I have used Raspberry Pi's a bit before and have kept reef tanks for most of the last 25 years. I am very interested in setting up a Reef-Pi system. So far, I have set up a Pi3 and installed Reef -Pi 1.5 (just because it is the stable version). I have got grips with controlling the relays. I am going to start connecting equipment up to the 8 relays that I have at the moment.

I have not completely caught up with all 228 pages of reading in this thread, but want to ask a few questions :-

1. How many features are available? I'm aware of the following -
   1. Temperature measurement and control
   2. ATO
   3. Power switching of equipment.
   4. PWM control of dimmable LED's
2. I see that PH measurement is happening. What else can we expect? Do you think we will get to the point of Nitrates, Amonia, Calc etc? What are the limitations?
3. I can't find a guide for setting up an IO expander - I see myself needing one.

Thanks to all the guys doing work on this . It's fantastic!

Des

​

Welcome to reef2reef and Thank you for considering reef-pi. I vaguely remember a thread on reef-pi in South African reef forums.
There’s no support for gpio expander yet. Other than what you have already mentioned , doser and ph monitoring capabilities are functional as well, but not documented ( will be available in a month or so). I am running the ph monitor for weeks now and you can see the results few posts earlier. You don’t have to read all 200 pages to build a reef-pi controller. Use the docs in website to get started and ask questions here.
Other than doser and ph, macro (aka feed mode) , data import/export and light get acclimation are features slated for 2.0 release. I have some long shot plans for 3.0 as well but it’s too soon to talk about them. Current focus is to ship 2.0 features well tested and documented

Again, welcome to r2r, your home for all things reef keeping. You’ll love it here. I’d love to know about your tank and live stock :-)

 

[Ranjib]

Hey all, especially Ranjib.

I am from South Africa and have recently stumbled apon this project. I have used Raspberry Pi's a bit before and have kept reef tanks for most of the last 25 years. I am very interested in setting up a Reef-Pi system. So far, I have set up a Pi3 and installed Reef -Pi 1.5 (just because it is the stable version). I have got grips with controlling the relays. I am going to start connecting equipment up to the 8 relays that I have at the moment.

I have not completely caught up with all 228 pages of reading in this thread, but want to ask a few questions :-

1. How many features are available? I'm aware of the following -
   1. Temperature measurement and control
   2. ATO
   3. Power switching of equipment.
   4. PWM control of dimmable LED's
2. I see that PH measurement is happening. What else can we expect? Do you think we will get to the point of Nitrates, Amonia, Calc etc? What are the limitations?
3. I can't find a guide for setting up an IO expander - I see myself needing one.

Thanks to all the guys doing work on this . It's fantastic!

Des

​

I do not have any plan to integrate nitrate, ammonia testing. The commercial probes for these are simply too expensive and from my experience I felt these are only required in the very beginning (except may be nitrate). If ammonia is shooting up, I would assume it will impact ph as wel and whole lotta other things

 

[Ranjib]

would I need a rtc added to it or if connected to wifi would it supply the correct time?
if wifi went down would that cause issues?
all new to me as you can tell by the questions

an rtc is a good to have thing, not a must have. I personally don’t use them, and don’t see a compelling reason to have one. Use ntp to sync your time and unless your pi is switched off it should not impact the time. WiFi is only required during setup, and if you want to access the ui from other devices (tablet , pc , phone etc) . None of the reef-pi featuree requires internet , other than data logging to adafruit.io, which is optional and disabled by default

 

[Ranjib]

Too much technology . Time for some corals

I have high hopes for my sps , now that I have doser and ph monitor automated

 

[LionHeart2017]

Thank you Ranjib, I've now got some stuff ordered, got a pi zero w with 4gb SD, got 40 female wires, 8 channel relay that are 4 side by side, a ULN2803A and PCF8563T RTC, these are all for a 8 way power box using IEC plugs, skimmer with a shutdown time each day for dosing manual elements, 2 tunze powerheads with hope to have some kind of on/off cycle with the powerheads as they have no external control, and timing my LEDs to go on and off, overall hoping to tidy up the mess of wires with this first build.

 

[Ranjib]

Thank you Ranjib, I've now got some stuff ordered, got a pi zero w with 4gb SD, got 40 female wires, 8 channel relay that are 4 side by side, a ULN2803A and PCF8563T RTC, these are all for a 8 way power box using IEC plugs, skimmer with a shutdown time each day for dosing manual elements, 2 tunze powerheads with hope to have some kind of on/off cycle with the powerheads as they have no external control, and timing my LEDs to go on and off, overall hoping to tidy up the mess of wires with this first build.

Nice. Next time get a bigger as card. Make sure you choose the lite raspbian (without GUI) for 4gb as card based builds

 

[Ranjib]

Nice. Next time get a bigger as card. Make sure you choose the lite raspbian (without GUI) for 4gb as card based builds

You’ll also need a mini hdmi to hdmi connector and micro usb to usb connector (or micro usb based keyboard) to setup the pi

 

[LionHeart2017]

Nice. Next time get a bigger as card. Make sure you choose the lite raspbian (without GUI) for 4gb as card based builds

Will do, thought 4gb would of been enough, didn't realize, luckily I was planning just to connect with my laptop ( which I had to buy as haven't had a pc in the house last couple of years lol)

Here's what I'm running

 

[Ranjib]

Will do, thought 4gb would of been enough, didn't realize, luckily I was planning just to connect with my laptop ( which I had to buy as haven't had a pc in the house last couple of years lol)

Here's what I'm running

Very nice :-)

 

[LionHeart2017]

Going through a lot of maintenance ATM, got infested with vermatid snails, having to manually remove hundreds of them is not fun and very time consuming but I won't give in to them lol

 

[Ranjib]

Going through a lot of maintenance ATM, got infested with vermatid snails, having to manually remove hundreds of them is not fun and very time consuming but I won't give in to them lol

Ahhh...I hear you. They are ugly. Thankfully they dont do any direct damage. You can reduce nutrients and systematically (mechanical) remove them . Make sure you remove the base.

 

[SDchris]

Why? I have calibrated the probe using standard solutions from atlas scientific . It’s a three point calibration. I have to have reason to doubt them. I can cross check with titration based test, but as of now, I don’t see any compelling reason

At pH 6.2 - 7.2 calcium carbonate (rock, coral skeletons...) will start to dissolve.
The alkalinity / calcium additive your using will not drive pH that low.
And if your pH was chronically low, you would need to fix the cause, rather then mask it with limewater.
This graph was more typical of a calibration / software issue.

The first graph (page 115) looked more like interference. Why! because it started with a nice smooth line like you would expect. Then you get the spike and drop, after which the result bounces around. It should not bounce around like that, even after adding an alkalinity supplement that might lower pH. Also the pH was below what you could get it to go even if you massively overdosed an alkalinity supplement.

Maybe post your graph in the Chemistry Forum.

Chris

 

[Ranjib]

At pH 6.2 - 7.2 calcium carbonate (rock, coral skeletons...) will start to dissolve.
The alkalinity / calcium additive your using will not drive pH that low.
And if your pH was chronically low, you would need to fix the cause, rather then mask it with limewater.
This graph was more typical of a calibration / software issue.

The first graph (page 115) looked more like interference. Why! because it started with a nice smooth line like you would expect. Then you get the spike and drop, after which the result bounces around. It should not bounce around like that, even after adding an alkalinity supplement that might lower pH. Also the pH was below what you could get it to go even if you massively overdosed an alkalinity supplement.

Maybe post your graph in the Chemistry Forum.

Chris

The very first graph was during calibration. My local reefers suggested that I may have an elevated CO2 issue, but I have no way to confirm that. I 'll definitely post this to the chemistry forum, as well as run a titration based test (API). Thanks for the hints, I really appreciate it. Some of my local reefers told me not to worry too much about it, if the daily peak is at 7.5-7.8.

 

[CL Ingus]

Wo

In fact reef-pi is modular by design. You can use any single module to roll up a monitor/controller with only one specific feature

i was wondering about this as a method to distance the power strips from the main controller. Instead of having a second pi operate by itself can it receive gpio commands wirelessly from a main controller?

 

[CL Ingus]

Does anyone have an opinion on a solution to skim 5v power for the pi off of 110AC. MOSFET, buck,etc? Looking to house the pi along with power outlets.

 

[Erica-Renee]

Does anyone have an opinion on a solution to skim 5v power for the pi off of 110AC. MOSFET, buck,etc? Looking to house the pi along with power outlets.

you will need something like this...
https://www.amazon.com/DROK-Switching-Transformer-Converter-Wide-range/dp/B01LENMPUO