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nickjacob
04-26-2013, 09:36 PM
I am having Issues with my bell siphon. I have a 3/4in. standpipe and a 2in. bell. There is no issue getting it triggered, but it stops prematurely. The water level only drops 2-3 inches below the top of the standpipe. The seal is good and we have experimented with the height of the bell in comparison to the standpipe. It stops and starts fine. We had issues with starting it but now it stops early. Can anybody help?
Thanks

bsfman
04-27-2013, 09:56 AM
I am having Issues with my bell siphon. I have a 3/4in. standpipe and a 2in. bell. There is no issue getting it triggered, but it stops prematurely. The water level only drops 2-3 inches below the top of the standpipe. The seal is good and we have experimented with the height of the bell in comparison to the standpipe. It stops and starts fine. We had issues with starting it but now it stops early. Can anybody help?
Thanks

Can you increase the rate of flow into the GB? Or are you at full force already?

Oliver
04-27-2013, 06:46 PM
Most likely you have too much water going into the grow bed for the rate going out. You can either decrease the inflow or you can extend the down pipe below the bottom of the grow bed to increase the draw down rate.

As the water level in the grow bed goes down it produces less draw down and the out flow slows. At some point, the out flow through the siphon has slowed to the same rate as the inflow. At that point it reaches an equilibrium and the water level in the grow bed stays constant. To increase the outflow the draw down pipe below the bottom of the grow bed must be long enough for the weight of the water in it to keep the water moving at a higher rate than the water coming into the grow bed.

If the bottom of the siphon below the grow bed is connected to plumbing that runs horizontal to the fish tank then make sure it does not at any point in its run go up hill before reaching the fish tank (or whatever you dump the water into). It must run downhill for the full length of the run. Make sure that the end of the siphon drain is open and not in the tank water at any time. Make sure the end of the run is several inches (at least 6 inches) below the bottom of the grow bed.

A two inch bell housing is small for a 3/4 inch stand pipe. How much room between your funnel on the top of the stand pipe and the bell wall? Could be some restriction there.

nickjacob
05-02-2013, 12:50 PM
thanks guys... The flow is really low. We moved from a 2 in pipe to a 1.5 in pipe and it still stops halfway down...Flow is slow so I'm not sure what the problem is...To answer your question we have tried it on full blast but it didn't do anything...Thanks for offering ideas!!!

Bob Vento
05-06-2013, 09:33 AM
Have been using one of these flawlessly for well over a year. Periodically have to clean they tubing and change the bottle once in a while but other than that it was cheap, functional and readily available free parts. Check it out


http://www.youtube.com/watch?v=oDzcKgWLRf0

hawkiye
05-06-2013, 10:09 AM
I just had the same problem. Are you getting a trickle of water continuously draining out of that bed? if so you are getting to much back pressure somewhere to start the full siphon and it is just acting like a continues ebb and flow. I discovered that when I raised my drain header a little on one end to make sure it was going downhill that I inadvertently raised the pipe under the grow bed so it was slightly up hill. Solution lowered the drain header a little so it would still be down hill but so the pipe coming to it was also a little down hill. I am using 3/4 stand pipe also with a 2 inch bell.

JCO
07-27-2013, 11:42 PM
So did you figure out your bell siphon problem. If so, enlighten us and the world so we don't make the same mistake/s :mrgreen:

Aufin
07-28-2013, 11:09 AM
Gentlemen .... and ladies ....... not trying to start an arguement here, just wondering .... what's so special about using a Bell Siphon? I can see where it looks a bit "cleaner" around the grow beds, but, so what? I originally set up my small system with Bells, but continually putzing around with "this must be here", "this must be this long", "drop this far", etc., I scrapped it all and went with old fashioned siphon hoses hanging on the outside of my growbeds. Cheap and easy and I haven't had a problem, and it's very easy to raise or lower the max. water level in my beds.

Not saying one is better than the other, just wondering why we always try reinventing the wheel when something tried and true works just fine.

Just my $.02 worth ..... I could be wrong, so I would appreciate someone enlightening me on this subject.

keith_r
07-29-2013, 05:42 AM
loop siphons work fine.. you still need to take up some real estate in the growbed for a guard..
in big beds, i like bell siphons, small beds get loop siphons