Backyard Aquaponics
A place to discuss aquaponics

Hi all,

I made a bell siphon after watching some of the youtube aquaponic ponds. Here is the video I followed.

https://www.youtube.com/watch?v=J4i-jZoynUs

I followed that step by step even the size of the tubing. I am using a cement mixing tub as a grow bed to hold media.

http://www.homedepot.com/p/Plasgad-Medi ... 5yc1vZaq89

When I first made the aquaponics system, the siphon was not getting started correctly so I adjusted the distance between bell and the stand pipe. Then I found out that the bell itself was not staying down to the bottom of the tub because the bottom was somewhat warped.

Once I put in the substrates (Hydroton), it seems to have helped the problem as the siphon ran correctly. However, everyday after I get home from work, I would find the siphon just running and not stopping correctly. I adjusted the flow rate to turn down the water going into the GB, and then it would run normally.

Then, I decided to add some GrowStones into the GB so there would be more weight. Again, the system will work throughout the night and even in the morning and I would come home and find it not working. This morning as I was adjusting the flow rate, I find that the siphon no longer even starts (i was trying to push down the bell and the media guard to see if they moved) and the water overflooded from the top. I shut off the siphon and I will probably have to fix it later.

So my question is:

Do you guys think the media has something to do with it? WHen theres water in there, most of the Hydrotons and evne growstones just float up, and I am afraid some of it might have gotten inside the bell/media bc nothing is being held down.

Do you guys think its the tub? its warped on the bottom so sometimes the siphon is on the bottom sometimes its not, I feel like with the substrate / water in there this should be a problem?

Any other recommendations? Please I need your advice as I am relatively new at this. Thanks

Do you have a picture of your media guard? That is often the culprit. Especially if you drilled round holes instead of grinding slits. Hydroton settles right into the round holes.

I am currently at work, but that maybe the problem. Media Guard is a 3" pvc and I drilled holes instead of slits like you said.

Also, the pipe on the drain off the bottom of the GB is 45 degree and not a 90, probably will chang ethat too.

It sounds like you need to rework our media guard. You can add slits with a saw. If you have a table saw or chop saw you can make short work of it. If you have to use a manual saw it can be done but will take a while because you'll need to make a lot of cuts. Another thing you can do is put a rock or some other heavy object on top of your bell inside the media guard to hold it down. Also, make sure your drain pipe has a drop all the way to its exit... meaning... there should be no standing water inside your drain pipe because it has to travel up hill along its route to the sump tank or whatever it falls into. This will often prevent a drain from starting.

Once you do all those things I recommend opening up the water to full capacity. If the water is coming into your grow bed faster than it can drain via the stand pipe you can turn down the water. As long as your siphon is designed correctly everything should work. Keep us informed.

Another thing that can happen is that you make slits in the media guard but not enough at the bottom, so that when the water level is down to minimum there will not be enough flow past the media guard and this could affect the syphon from breaking.
As for the initiation of the syphon, and also the break at low tide, ideally if you can get the system to run directly with the bell syphon outlet tube, without any bends or extensions, the better. I read this on a blog and it has worked for me. But these things are temperamental and in some cases I have put a 90° PVC coupling and it works. In my case it also helps to direct water flow into the sump tank.
Also I made o drilled 1/4" inch holes on the bell 1" above the cutout that came with my store bought bell syphon from Amazon, so that it would start sucking air as water level reached mínimum and that worked and is working super.
All of this is new territory and not a week goes by without some new lesson learned. Am still having trouble with high pH from the Growstone (9.2) and each time I add acid, a day later pH goes back up and even higer. My plants are yellow, although my fish seem happy. Started with guppies to get the system sickled, and someone gave me some koi, and they are fine.