Bell Siphon Problem. HELP!!

[james davis]

Hello all. I recently started my first aquaponics system and im having a problem with my bell siphon. It will seem to be working perfectly buy after filling the grow bed up the siphon wont start. It will just drain down the inside pipe until i move the outside of the bell a little maybe turning it a quarter inch then the siphon will start. it will then ususlly work for a few cycles untill stoping at the same part again. i know you all have lots of experience with aquaponics so any help would be appreciated. thanks.

[Jim Fisk]

Yup Jim,  the 90's do slow down the flow just enough to fill the tube and voila it starts. Mine work fine with one but if someone's flow is really slow a 2nd one always does the trick so I started including 2 just in case. So now I go thru twice as many 90's. Oh well. I see some use a "trap" under there but I find the siphon will "break" much quicker, as it should, if air can come from both directions, under the bell and back up the tube, so a trap can cause trouble and sediment collected in the trap over time can change the "tune" eventually.

Jim Kamen said:

OK, I'll chime in now.  I have had the same problem as James along with a host of other learning problems.  I did have to play with the design just a little and my siphon's are all working just fine.  I am not sure just what I did to make them work, but I don't really care.  As was stated earlier, most of us just want the fix, not the physics. I do think adding some length and elbows to the drain helped a lot.

Another thing I found was that the outer pipe is slightly smaller in diameter and does not fit over the bulkhead fitting completely.

I have six siphons working off one pump.  I used some old grow boxes as my bed. Yes I do loose some space but it was the least expensive way to start.

Now, if my Talapia would only get here.

[james davis]

wow you guys are awesome. I couldn't have asked for more info from just one question thanks to all for the help.

[james davis]

I Found after reading some of your replies that my problem was that I had a male and female electrical fitting on the bottom of my grow bed and the bottom of my grow bed just has the female fitting with water pouring out. I added a 3 inch tube to the bottom of my grow bed and it started siphoning by its self. I am now looking at building a new system and am considering  all of your comments. thank you all.

[Jim Fisk]

We are all happy to help James. Amazing how a a little tweak can make such a difference. There is a bit of Voodoo to it. Great thread. Twas fun and just think how many others will be helped by it.

james davis said:

I Found after reading some of your replies that my problem was that I had a male and female electrical fitting on the bottom of my grow bed and the bottom of my grow bed just has the female fitting with water pouring out. I added a 3 inch tube to the bottom of my grow bed and it started siphoning by its self. I am now looking at building a new system and am considering  all of your comments. thank you all.

[CArol Sheridan]

James I had the same  problem.After playing around and doing several things this is what helped  the most.  I was using a 1 inch drain pipe and on the top I reduced it to a 3/4 inch . It is working a lot better