The Bell siphon is a key component of the aquaponics system. In this video we will see: 1: The purpose of a bell siphon, 2: What it is composed of 3: How it works …


  1. Very glad I serviced the Auto Siphons. Yesterday the safety switch kept turning off the power. Still had power at 2 power points. The back up bilge pump was spraying water into the fish tanks and the 4 mm leak holes drained the grow beds. This keeps the grow aerobic. Power was off for most of the day. Late in the day ran extension leads to the aquaponics. It was only at the end of the day that I discovered that the fish tank had leaked onto a power board and caused shorting and arcing. Fixed the filter which caused the leek and removed the extension leads. The aquaponics was without power for over 8 hours. The trout were quiet last night but today they are leaping out of the water at feed time. If the grow beds were flooded for over 8 hours they would have become anaerobic and accumulated methane and hydrogen sulfide which are extremely toxic to fish. The leek holes prevented this happening and thanks to Affnan's research and auto siphon design my trout are fine.

  2. Just finished servicing my Auto Siphons and forgot to mention rotating the media blocker. Plant roots can block the holes in the media blocker (outer shroud) and by rotating without lifting the roots are cut and cleared. I do this when the stand pipe is removed and if the roots are long I flush with the hose or remove by hand until all clear. Sometimes root growth can make it difficult to rotate and this is why I do it every time I service the Auto Siphons.

  3. Well done promoting Auto Siphons, they are amazing. I use Affnan style Auto Siphons (Thanks Affnan) with a 40 to 25 mm adapter on top of the stand pipe and a 4 mm leak hole at the base of the stand pipe. The adapter allows a wide variation in flow rates and avoids equilibrium flow and the leak hole empties the grow bed during a power or pump failure. The small hole is prone to blocking and my weekly service includes clearing the hole. My power-fail back up sprays water into the fish tanks only and if the grow beds retained water they would become anaerobic. I still enjoy hearing the gurgle as the siphon breaks.

  4. I think your explanation of how the siphon stops is slightly inaccurate. My understanding is the air tube, or a hole near the bottom, is just to provide a slow leak. It's only once the water level reaches the bottom lip and a large bubble of air is allowed in that the siphon breaks. Without the air leak, there's a risk that a pocket of air can restrict the water flow and leave the siphon in equilibrium.

    I've had success with a bell siphon made from a plastic drink bottle with a hole drilled in the bottom and a screw fitted in the hole that acts as both a handle, and a valve to control the leak.

  5. We are always waiting for your nice videos. I wanted to know if there is any organic substitute for Iron deficiencies that we can use for our system. Also if there is other organic substitutes for the other deficiencies in minerals needed for the plant.