Not a bot (we have to say that now, right?
)
Some updates as promised on the build. Still not scaped btw - but hoping to get some time this weekend.
First thing is I knew I wanted a Time of Flight sensor in the sump for an accurate level measurement for the ATO, AWC trim, possibly see filter fouling, and as an extra safety layer. The big question was how to seal it from moisture.
I figured the easiest way would be to seal the sensor inside a printed case, with some desiccant, and a glass cover. Attempt 1 went horribly as the printhead collided with desiccant and then dragged it across the pcb destroying my first sensor.
Attempt 2 went much better as I made the box deeper, and siliconed a glass microscope cover slip to it.
But - this didn't work, since I increased the gap from the sensor to the glass - there was some crosstalk with the glass reflecting some of the signal. So on to attempt 3. This time I skipped the desiccant entirely having failed the first 2 times, and printed a small adapter to limit crosstalk, and covered it with an iphone camera glass, then expoxied the entire pcb.
This worked, and no worry about moisture killing the sensor! I installed it in a stilling well so any turbulence is smoothed out, also pictured is a FSIR02 sensor for triggering an emergency if the sump level ever went too high. Also a mounting hole for the glass
pH probe so its somewhat protected from me.
I then also got these nice flood sensors from aliexpress that I mounted on both back corners of the cabinet. I like them a lot as they can be mounted with the pins in any position and they feed right back to the main controller to shut off the pump if needed.
Then began the wiring and testing....
This easily took many evenings to get done, but I finally (mostly) got everything in a state that I'm okay with.
ATO supply + fert dosing. Also not pictured is the liquid sensors on each of the 3 bean animal drains, and one on the chamber 1 glass to detect if the first filter is in need of cleaning.
ATO + flow sensor, extra mechanical float as backup layer, AWC Pickup, EC Probe, Return Pump, Low float sensor, temperature probe, and stilling well (FSIR02 high level, pH probe, ToF sensor).
I also got the first version of the weir box printed, and used a small o-ring to seal it against the bulkhead so its a press-fit and still removable.
After this - I really wanted to address the loc-line fittings that I showed before that I absolutely hated the look of.
I ended up ordering a bunch of different tubing and fittings from Aliexpress to try and put together something better. First up was clear acrylic - I didn't mind this too much, but it still looked bulky to me, and wasn't too sure about the clear.
I then tried a set of black - which was decent, and blended in a bit more - but still a bit obtrusive.
In the end, I went back to my trusty printer and modeled up something a lot sleeker. It's a 2 piece design, the first spins onto the bulkhead, and has a recess so it fits flush against the glass. The second has a tab and tightly clicks into place with 3x 6mm jets, with the top and bottom one angled upwards about 10degrees or so.
A LOT sleeker IMO, time will tell if the flow will be adequate (orst case, I can fall back to one of the other options)- but the beauty is I can print out revisions as needed within a few hours. And as a bonus, if I see the need later - I put in small recesses on the side of the jet channel that will accept a moss holder if I really want to hide it more.
The sump area is pretty much done with the exception of lines to the fert bottles, and final overflow pvc pipe termination in the sump. I may also swap out the main LED power supply as my smart plug is showing an idle draw of about 7-8W being an older unit (modern units being <0.25W) - so less waste, less heat in the cabinet. It would be ideal to do it now before the plumbing has water in it.
I've also got a start on the home assistant dashboard - but still some things to sort out:
Also have a display of sorts in the works - probably not at all necessary, but for the fun factor. More on that next time. I think I'll need an entire thread to explain all the automations, and why certain sensors were picked.
Otherwise, substrate is in the tank - and the basement mixing/co2 cabinet is done and painted - so work will begin down there soon too. Starting to see the light at the end of the tunnel!
