Backyard Aquaponics
A place to discuss aquaponics

So i bought a premade siphon setup from aquaponicssource.com. The odd thing about the setup is the outer pipe(not the gravel guard) has two cutouts at the bottom for water flow, but both are only about 1/2' tall. Many i've seen have at least 1" to 2" teeth. i realize this means im likely draining down further which i guess is fine. but could this be contributing to my siphon not stopping. I realize there are a ton of factors including my outflow pipe length, inflow rate, siphon design etc but really curious what people think about the 1/2" high drain holes. Might add a snokel if people think that could help.

so if you look at this stock photo at the outer pipe on the far right, you can see how low the cutouts are.

Inlet of water might be more than what is being siphoned and thus it never reaches the slit to break the airlock.

It's designed fine.

Just slow down the water flow.

From my experience with siphons, having the water inlets at the base of the bell causes two issues:

(1). It makes it much harder to get the siphon to stop, especially if the siphon set-up is in the lowest part of the GB. With the slots at the base like that, tuning the flow down enough to get the siphon to stop greatly reduces the siphons operating window and can make them very finicky and unreliable.

(2). The second issue is that it doesn't allow any solids to settle in the GB, which may be okay if you have a swirl or radial flow filter after the siphon and before the FT, but otherwise it means the solids stay in suspension in the water and are returned to the FT.

If you don't have any mechanical filtration (as above) between the siphon and the return into the FT, then I would recommend making a new bell with the slots further up the bell so: (a). The water isn't being drawn from the base of the GB, and (b). So that when the siphon cuts off there is still 40-50mm of water in your GB.

This improvement will not only make the siphon easier to tune, it will also allow solids to settle in the GB, where worms and other natural processes can release the nutrients contained in the solids, as well as giving the plants in your GB's a reservoir of water should the pump fail and be off for an extended period.

Colum, i knew turning the inflow down would probably work, but i was at the minimum flow i needed to turn my tank over once per hour so i didnt want to do that. Decided last night just to add a simple snorkel using 1/4"OD vinyl tubing into a 1/4" drilled hole. Fit perfectly and no need for extra silicone around the tube. Zipped tied the tube down to about 1" above my bell cutouts. works fine now.