The CT-1 Short Cycle Timer is the timer that I have been using for my aeroponic grows for the past year. I have used this interval timer with both high and low pressure systems and never had any problems with it. I run this 1 minute on and 5 minutes off. My roots are slightly moist when the next cycle begins and have nice fish bone structure.
I read a review on Amazon where a guy claims it killed his crop from over watering. All I can say is he must have gotten a faulty timer or more likely some kind of root rot killed his crop. Even with completely submerged roots in a hydro system water will not kill a crop unless there is a pathogen present. I am sorry for his loss, but I still feel this is the best aeroponic timer for the money. Even more expensive CAP timers have been known to be defective right out of the box.
It seems there are a lot of negative reviews on this timer which I believe stem from wrong set up or plugging in something that draws too many watts.
All I can say is that I run 3 of these timers and have never had any problems with them.
If you buy this make sure it is set up and it is cycling right, otherwise you have 30 days to return it. One thing to mention is this timer has day or night settings or both. You want the sun and moon icons to both be showing on the display screen otherwise this timer will run your cycle for 12 hours and shut off for 12 hours. Other than that this timer is highly adjustable for running in seconds,minutes or hours. You could actually run 1 second every 24 hours if you wanted to.