Thanks for all the help everyone. I just wanted to throw out a little update now that I'm on my 4th crop with this setup. Every crop gets better!!!!

I fought hell getting the flimsy tubs to not leak at the drain hole, but I won the battle. There IS an issue with some standing water, but I have everything in their own pots so it evaporates in about an hour. My main problem came from the flimsy plastic. I had to reinforce the table and provide supports for the down-tubes to strap onto. Otherwise everything flexed and twisted when I moved the pumps to change the water. Since everthing is run to one reservior, I can't do the perpetual harvest and flush just one single tub. That's okay, it leaves a good day to completely clean out everything.

The real benifit to this system is the three seperate tubs. One 25 gallon reservior handles everything. It takes about 15 gallons to fill one tub (leaves 10 gallons to prevent the pumps from sucking air), then it drains and 15 minutes later I use the same water to fill the next tub. This requires three sperate pumps and three timers, but it's way less water I have to run through the piss-dribble RO filter. Way less nutes too. I have to top it off with about a gallon every day, and check the nutes every 3 days. Then I clean the reservior out every 2 weeks and it's good to go.

I can easily fit 12-16 big plants, depending on how long they vegged. My very first crop was from some bullshit online seeds and they were 90% male. That sucked. My second crop was from some mostly good seeds and about half the crop was DANK. The other half of that crop looked like seaweed, but I'm still learning. What I learned was: get good clones! The third crop was an all-star affair. Everything was good. The fourth crop got started late and I basically vegged them for 2 weeks before they went to flower. This yield will be relatively small. The 5th crop is currently in the veg room and it's getting big. It will have a huge yield compared to the rest, but I'm getting better with every cycle.