I hear my tomatoes calling me to add some posts or a cage right now. I just was out there and they are more then ready to get staked.

How are you draining the two book ends?

For myself I would run it just like the sun in your parts. Off at night. See how it works for you. But never turn off any air to the pesky gold fish.

If the pots take 15 to fill and the bed 30. What happens to the pots for the 15 minutes. Looks like they fill and drain almost twice to the main GB. So they will be getting twice the feed per day? If I had a timer I would change it up to 30 minutes on and 1-1/2 hour off. During the off time the beds should be draining and let the O2 to be sucked in. I have drowned too many plants. It was my number 1 problem. Our plants can go a long time without new water as long as the media is wet. I actually measure my plants when doing any testing, before and after.