Another reef-pi build

[tbh1]

Hi folks!

I recently set up my first reef-pi (for my first reef tank) and I thought I'd share my experience. I'm a software engineer by trade and I enjoy tinkering, so I was excited to find out about this project! Hopefully I'll be able to contribute going forward.

Build details:
- standard components (rpi4, pca9685 for lights, and ADJ power strip)
- single controller box with 12v, 10v, and 5v circuits
- two temperature probes (one in display, one in sump)
- dedicated float switch for sump overflow
- single 0-10v jack controlling two Nicrew 100w lights

Enclosure

I've been printing various parts for my tank build (overflow lid, light mounts, pod hotel, etc) and wanted to try designing a custom enclosure. I haven't made anything this complicated before so it was a good learning experience. Everything is tailored to my specific components but I'm happy to share the models.

And here's how everything looks wired up. Not the cleanest job but I'm happy with the results.

Lights

I initially planned to have each Nicrew 100w on a separate jack to control independently. However these lights suffered from some major jitter below ~50%, even with the PCA9685 driver set to 1500 . I ended up going with a single 0-10v jack and using the extra space for a simple low-pass filter. Luckily the Nicrews include a 0-10v output jack for daisy chaining! With the LPF I can get a very steady output down to 7%, where the lights just shut off.

Here's a pic of the LPF I took while testing, I believe the capacitor is 1uf.

Temperature

I'm using two of the cheaper stainless steel DS18B20 probes that I wrapped in heat shrink and capped with some extra silicon - we'll see how long they last. I've had some issues getting both probes to register, it seems random whether either or both actually show up after a reboot.

Emergency Shutoff

I'm currently using the XPAqua Duetto ATO for top-off, but I wanted to include a redundant float switch to directly control power to the ATO. I have this float switch wired in via an AUX jack using one channel and ground. I might rig up a second float switch to the unused channel to handle water at different levels.

Right now I run my ATO and skimmer on separate reef-pi ATOs with the float switch as a reversed Inlet. This way reef-pi will kill my ATO if it dumps too much water in, and it automatically shuts off my skimmer when e.g. I turn off the return pumps.

Monitoring

I LOVE that reef-pi exports Prometheus metrics! I have Prometheus and Grafana running on my home lab so integration was super easy.

Next Steps

I'm pretty happy with where my reef-pi is at, but I definitely plan to include a PH probe. I'm currently waiting to see if ML Reefkeeping's PH board will be in stock after this month, if not I'
I'm pretty happy with where my reef-pi is at, but there's definitely a few things left to do:

- PH probe: currently waiting to see if ML Reefkeeping's PH board will be in stock
- Wave makers: I have two Jebao SLW-20's I'd like to control. I'd like to poke around with an NRF24L01 to see if I can use the slave mode directly
- Dosing pump: I'm currently trying out all-for-reef so not a huge need at this point, maybe in the future

And here it is tucked away in the back of my sump area where no one will ever see it

 

[DanTheReefer]

Great build, I like the custom enclosure and how nicely everything is laid out.

I think the temp monitoring in the display and sump is a good idea. Biggest issue with my RP is the temp probe is in the sump while the heater is in the display (like to keep an eye on it) - if I turn off the return pump and forget to turn it on the RP loses the feedback loop.

I was looking at nicrews by the way, do you like how they’ve been performing, good coral growth etc? Can you share pics of how it interfaces with those as well?

 

[Weasel1960]

nice job. Maybe in the future you will have a control cabinet so you can show it off.

 

[tbh1]

I was looking at nicrews by the way, do you like how they’ve been performing, good coral growth etc? Can you share pics of how it interfaces with those as well?

I honestly don't have a good frame of reference for how these compare to other lights, but they seem to be doing a good job for me. I have them mounted under cabinets, they're lower than ideal but the spread is good and I don't really notice any disco ball effect. The fans can be a bit loud but it doesn't bother me - apparently removing the top plate helps a lot with that. An added bonus for me is that my LFS runs Nicrew 150s over all of their frag tanks.

As far as integration, anything other than the 30w unit has a 3.5mm input and 3.5mm output for 0-10v. I just run one line from the reef-pi to the first input, and run the output to the second unit's input. Light controls work great after adding the LPF circuit.

Here they are over my 40 breeder. You can see on the left two power cables and one 3.5mm cable for 0-10v. The second unit's power cable and a short 3.5mm cable run between the two units.

nice job. Maybe in the future you will have a control cabinet so you can show it off.

Thanks, hah ya I hope so. I've had a ton of fun building out this system, can't wait to upgrade.

 

[Weasel1960]

I honestly don't have a good frame of reference for how these compare to other lights, but they seem to be doing a good job for me. I have them mounted under cabinets, they're lower than ideal but the spread is good and I don't really notice any disco ball effect. The fans can be a bit loud but it doesn't bother me - apparently removing the top plate helps a lot with that. An added bonus for me is that my LFS runs Nicrew 150s over all of their frag tanks.

As far as integration, anything other than the 30w unit has a 3.5mm input and 3.5mm output for 0-10v. I just run one line from the reef-pi to the first input, and run the output to the second unit's input. Light controls work great after adding the LPF circuit.

Here they are over my 40 breeder. You can see on the left two power cables and one 3.5mm cable for 0-10v. The second unit's power cable and a short 3.5mm cable run between the two units.

Thanks, hah ya I hope so. I've had a ton of fun building out this system, can't wait to upgrade.

Nice looking setup. Maybe some of the excess fan noise is reflection off the cabinets and walls or vibration? Not sure how to correct reflection, felt furniture pads might isolate vibration at mounting points. Just a thought.

 

[Ranjib]

This is awesome :/)
Thank you for sharing your build details. That lpf use is a very common issue, We should include it in light controller guide

 

[Mindblock769]

Would you mind sharing your printing model? I have a friend that has a 3d printer, not sure if all models are the same for the software, but would like to send it to him.

 

[tbh1]

Would you mind sharing your printing model?

Sure, I've uploaded the thing files here. Your friend should be able to slice these for his printer. https://www.thingiverse.com/thing:4943121

 

[mike89t]

Sure, I've uploaded the thing files here. Your friend should be able to slice these for his printer. https://www.thingiverse.com/thing:4943121

That looks amazing!

 

[rajdude]

Now that's what I call music....erm....a reef-pi build!

Jokes aside, your build is very nice. I really appreciate good clean wiring and enclosure design..and yours is awesome!
I am about to embark on my own reef-pi build and you have given me some solid inspiration!

Kudos!