I finished the AWC system a month or two ago, and its been working flawlessly since.
Here is how the drain pump, emergency overflow and float valve are positioned overall. (The tubing with the tee and a valve at the end is just an outlet where I can draw water from the tank if I ever wanted to.
The drain pump is hooked up to a digital timer with settings for 20 daily water changes for a duration of 2 minutes at hourly intervals. (Its the tube that snakes all the way up and then down again)
I estimate that approxiametely 4.2 gallons of water are pumped out every hour based on the water height difference after the water pump does its thing. (LWH/231 = total gallons; 36"x18"x1.5"/231=4.2078 ) This occurs for 20 times a day, so 4.2 times 20 gives me a total daily water change of 84 gallons, which should mean its equal to a complete 100% WC and then some, more or less. If anybody sees an error with my calculations, by all means, please correct me.
The drain pump and emergency overflow shares the same tubing, which snakes into a drain in the bathroom floor.
Next is how clean water gets into the tank.
This is where it starts. It's supplied mainly by the gray tubing which is simply tap water (~50tds) and the blue line that tees into the gray line is for RO water if I ever wanted to supply that (~0tds). As you may have noticed, its quite soft either way.
The gray tubing snacks up into the transitional water holding bucket which stores water and is controlled via a float valve too.
The bucket itself also has an emergency overflow in case the float valve ever malfunctions.
There is a pump in the bucket which attaches to another set of gray tubing, which pumps water into the main tank.
And here's the float valve in the display tank itself.
So far, its been working flawlessly. The only problem I encountered was periodic condensation all over the gray tubing because of the extreme temperature discrepancy from the cold water line. (It's the same condensation that occurs in most toilets too) In my case, it wasn't too big of a problem. But if it stretches over something you might not want water dripping on from time to time, then it might be a problem. I could probably put some non-glass heater in the bucket itself to better match the atmospheric temperature, but I don't think it warrants it yet, so I'm leaving it at that.
I'll do a thorough breakdown for the total cost of the entire system when I get around to it. But a ballpark estimates put all the actual parts I used at around ~$50? This was not including all the parts I bought and never used for the actual build including the RO filter, 45gal water storage bin, electric solenoid, miscellaneous tubings and wires etc.