You may recall a few posts ago I was testing my overflow drain and it was a partial success. Once the syphon got running things looked great but the 1" pipe was not large enough to keep up with the inflow of my pump. If I had let things go there would have been quite a flood. So here is version 2.
As you may be able to tell I have gone with a larger pipe (2") and modified the position of the T fitting. What you can't see is that on the grow bed side there is no stand pipe so the drain will be pulling from the bottom instead of skimming of the top. This solves one problem in that I hope to minimize the amount of air that can enter the pipe and allow the drain to maintain syphon. The problem is the drain will empty the grow bed if the pump shuts down, solution raise the t-fitting to a height that determines the minimum water level. In order to make the height adjustable I installed a compression fitting so I can raise and lower the T-fitting height.
With the new drain in place and design changes complete all thats left is to test so I turned on the pump and sucked the air out of the syphon to get things running and it was a thing of beauty.The water level came up and the drain started to flow perfectly for about an hour... What I didn't account for was a less than perfect seal in the check valve it was ever so slowly letting air leak in and eventually breaking the syphon. Time to find a better check valve. While searching the google machine I couldn't help but think about the problems that would arrise if the drain ever failed which led me to "improving the design".
Version 2 and a 1/2:
I found a youtube video where a guy added a small pump to constantly pull air and water from the top of the syphon now thats an elegant solution. Of course in my typical over the top fashion I also added a filter to prevent the pump from clogging. The system has run for 24 hours without any issues. I feel very confident that this will run as long as the pumps do, in the event that something clogs or a pump does go out its my plan to add 2 float switches on the grow bed water level that will shut off the pumps if the water gets to high or low. This will let me sleep at night.
Always remember fellas "If women don't find you handsom, they better find you handy". I'll be sure to update you on the progress with the switches as soon as I get to them.