Follow-up, after trying it
Follow-up: I tried using an aquavalve to flood a 2x2' tray with 7 plants in flower, each in a 1/2 liter plastic cup with coco and hydroton. My tray was filled with hydroton to take up space -- 2'x2'x1" is about 2.5 gallons, but with the hydroton a flood cycle took a bit less than a gallon.
I tried using it twice, for a run of a couple days each. Both times the tray never really fully dried out, and in between the reservoir level kept slowly decreasing. (diagram: red lines are from flood cycles, cyan from when it should have fully stopped flow.) The first time I figured that I hadn't set the aquavalve up correctly, the second time I moved it to the front of my tent to watch it closely, made sure it was level, the silicone plugs were seated properly, etc., but the same thing happened. I wonder if slower water flow through the pot sock was part of it, adding smaller and more frequent flood cycles where the space inside the pot sock dried out before the tray, flooded enough to refill it, and then that spread to throughout the tray and kept it from drying out fully?
I decided that it wasn't a good fit for my setup. The hydroton is necessary to avoid flooding a massive amount all at once, but also massively interferes with moving the plants around at all -- if they are even slightly shifted, hydroton tends to roll underneath the pots, and getting the plant standing up straight again can be a pain. I tend to move them around for training, to even out the canopy, inspect the plants, etc., so that's probably a dealbreaker. I could see the aquavalve working really well in a dedicated base with a lower volume though, particularly if the plants' pots were in a sediment / root barrier rather than the aquavalve itself.
I tried using it twice, for a run of a couple days each. Both times the tray never really fully dried out, and in between the reservoir level kept slowly decreasing. (diagram: red lines are from flood cycles, cyan from when it should have fully stopped flow.) The first time I figured that I hadn't set the aquavalve up correctly, the second time I moved it to the front of my tent to watch it closely, made sure it was level, the silicone plugs were seated properly, etc., but the same thing happened. I wonder if slower water flow through the pot sock was part of it, adding smaller and more frequent flood cycles where the space inside the pot sock dried out before the tray, flooded enough to refill it, and then that spread to throughout the tray and kept it from drying out fully?
I decided that it wasn't a good fit for my setup. The hydroton is necessary to avoid flooding a massive amount all at once, but also massively interferes with moving the plants around at all -- if they are even slightly shifted, hydroton tends to roll underneath the pots, and getting the plant standing up straight again can be a pain. I tend to move them around for training, to even out the canopy, inspect the plants, etc., so that's probably a dealbreaker. I could see the aquavalve working really well in a dedicated base with a lower volume though, particularly if the plants' pots were in a sediment / root barrier rather than the aquavalve itself.
