IMO the most important parameter, and the fastest to change, is alkalinity.
My method is automate alkalinity - both testing and dosing - and then everything else can be tested weekly and manually corrected after testing
you can completely automate alkalinity for 500$ With KH Guardian. They were the first ones to bring automatic alk dosing to the market and their product has been out the longest. It’s got optical drip count sensors, magnetic stirrer, built in pumps, numerous safety feature, webserver for remote access. I like it a lot and much more affordable than a whole controller system that does 10 things I don’t need.
Kh guardian - $400
Wifi bridge - $25 from
Amazon
Reagent dosing container - $24
amazon
Reagent dosing container - $24
amazon
Fine micron prefilter- $20 from Vivid Creative Aquatics
Baking soda - stole from kitchen
Total $495
For 50$ more you can add the AIM-S which adds temp, salinity, and orp monitoring also
For 20$ you can add AIM which allows it to integrate into apex