gorbrickon said:
No air stone in the res. I was hoping that the splashing from the overflow drainage would oxygenate the water. I think my pH was too high before but I've got it right this time.
First, congrats on the fine build of the bottle system. I've seen it on the net in quite a few configurations.
If you've built it the way I'm familiar with, you've used the bottle cap itself as the holder for the bottle. If you also installed a retainer screen in the bottom of the bottle, it will hold the hydroton back while you unscrew the bottle about once a week and trim any root growth that has grown through the screen and out of the neck of the bottle. It's a low stress manner of root maintenance in that type of hydro system.
Feeding your plants often enough is necessary for two reasons; One, it will keep the plant from having to grow massive roots as a response to low nutrient or water supply. Secondly, it will help keep your root area at a more consistent temperature level that can be controlled via the reservoir temperature.
If the root area is drained for too long of a period, the temperature in the root area will move more toward the ambient room temperature and less as a result of reservoir water temperature. Depending on your ambient room temperatures, this could cause a fluctuation of both your pH and in turn, your nutrient uptake. It's really best to control your root zone temperatures via the reservoir water temperature and control that to optimize all-around plant growth.
Sorry for being so wordy, but the reasons for the various area volumes and pump timing needs to be balanced so that all the environmental conditions of the root mass can be optimized to favor your plants.
You might think about increasing your fill timings to something like one hour on, one hour off. The temperatures would maintain a more stable trend and your pH would be easier to balance also.
Of course, this is all just my opinion based on my experience.
