Backyard Aquaponics
A place to discuss aquaponics

I've got a weird, issue with one of my bell siphons. It works perfectly normally, starting and stopping every time. However, since my small AP set up is in my bedroom, I turn off the pumps when I sleep. In the morning I turn the pump back on, and one of the siphons(I've got two growbeds) doesn't start, it just constantly dribbles water.

I fix it by putting my hand over it for a second which seems to fix it, and it continues to work just fine all day until I turn on the system again the next day. Any ideas why just the first "start" might be failing?

Levi try increasing the flow slightly, if there's not enough water flow, the siphon wont start and too much flow, the siphon wont stop.

You might just need to add a bit extra to the drain side of the siphon. Either a bit more pipe or an elbow.

Hmm, I'm out of elbows, maybe I'll lengthen the horizontal bits. Its worth a try. Still strange though, I wish I knew why it only fails the first flush.

Is it to do with slightly floating? whats the space between the top of standpipe and top of siphon?

Probably about an inch I think. Its been a little while since I made them so I'm not 100% sure.

Maybe a bit of trapped air which you help clear by putting your hand over it.

Put a elbow in it 45 or 90
Let us no how you get on

Its actually got two 90 degree elbows on it.



Lengthening the horizontal bit didn't help. Oh well, I'll just write it off as a mysterious *feature* of my system.

Hey hope I'm not too late here
Just turn the elbow
The horizontal doesn't need to be longer but the ninety at the end should be turned horizontal or even slightly over.
Good luck

The siphon in my IBC display system used to do the same. It would run perfectly all week, then on Saturdays I would turn the pump off so I could siphon the FT floor clean, then not every time, but occasionally when I'd restart the pump it wouldn't kick in at the top of the flood cycle, but I didn't want to mess with the flow rate because I knew it worked flawlessly all week. I found if I slightly lifted the bell to create a little more suction, then dropped it, the siphon would then kick in and work perfectly for the rest of the week.

Under the siphon the pipe did about a 6" vertical drop, then there was a 90 deg elbow with about 4" of horizontal pipe after it. I changed the 4" length of pipe for a 6" length... it hasn't missed a beat since... starts every time I restart the pump...

...so 2" makes a big difference... my wife has told the same thing before!