Your thread was a good read it's coming along well. And I definitely understand where you are coming from with doing the software yourself.
The last coding I did was over 10 years ago in high school and I've only used HTML, basic and a bit of python so Im sure I could teach myself again with a bit of effort. If I go with pre made software it will be something like the one in this thread which is open source, so I can teach myself the language used and have a good understanding of the system. Wiring anything electrical (especially 240V) is 100% new to me and a bit daunting so that will be a new experience.
Initially I want temp monitoring (I live somewhere too hot for a heater so I don't care about control, I just need to know if my chiller bites the dust ), 16 controllable outlets which I can assign some tasks to and dimming for my 3 Mars aqua lights (at some stage it will be 4). And I would like it all to be controlled / displayed on a tablet.
In the future I would like to add a solenoid on my RODI with a bunch of float switches to do automatic filling of my top off reservoir and general ATO functions. Then further down the line pH, salinity and ORP monitoring would be awesome but not required.
I also use aquarimate to monitor my parameters and remind me about tasks but I like how you included it in your software so I may consider something similar once I am happy with the majority of the controller.
I can tell you that electrical was new to me. People would be loling at me if they watch me work on the wiring. I did some reading, wire, reading, looking at the wires, read. I spent like a week with the whole unit wired up but never plugged in. When I did decided to be brave and test the outlet I used a cheap plug in led and had the whole system plug into a surge that I was ready to pull out of the wall in case of any issues. With that said my outlets been running for 2+ years and *knock on wood* no issues yet. Now the equipment that draws the most is my heater and I only been running that for about 3 months now; granted the system doesn't control the heater just yet.
Python is easy to learn or at least for me it is. I never knew python until I started this project and I been picking it up quickly.
The temp was the easiest to do. The DS18B20 is cheap (I got a bag of 5 for like $9). I use this site to help with code for the temp code -
https://learn.adafruit.com/adafruits-raspberry-pi-lesson-11-ds18b20-temperature-sensing/parts but I don't use all of their parts. I have my code check the temp every min and then log the temp every hour on the hour into a mysql database.
I'm still debating where I want to go next with controls. I need to work on the current system and clean up many stuff but I been thinking of either controlling my RW4s power heads (even started looking into that) or controlling my Kessil 360 (but I have the Kessil controller so no rush here) or handling a ATO.
I'm not one to share my code freely but I don't mind helping pointing someone in the right direction. Its not that I want to sell my code but it something I'm not willing to share or at least not share at this time. Now if I use any open source code or public code within my code I do share that freely as well.