Backyard Aquaponics
A place to discuss aquaponics

les has posted a list of pipe diameters to pump inflow rates that covers this in depth

...it happens to be the original post that started this thread

So why didn't you link to it Les?

ok here is a question
is there a minmum drop needed or does it just have ot be lower than the gb to work ?

ie i am thinking of burying my sump and sitting my GBs on the ground (or raised up verry little )as i am young and dont mind bending so will i need to dig half way to china to have sufficient fall from the GB to the sump to get it to work ??

CHeers

more drop more flow / easier initiation................i think

Normally there is a minimum 300mm drop from the top of the water level in the GB to the base of the GB...so as long as the horizontal distance isn't great, then the water will flow...just remember those famous words:

hmmmm well thanks guys ive been thinking of ways to try and reduce my expences, and was trying to eliminate the need for building GB stands and bases

but maybe ill need too

IMHO siphons are great.

However flood and drain using timers with expanded clay are virtually foolproof!

I will agree with that

Some interesting Siphons from the past here

http://www.sewerhistory.org/grfx/compon ... ushtk2.htm
http://www.sewerhistory.org/grfx/compon ... ushtk3.htm

Click on the pictures to see the full size images.

I know the links say sewer but it seems they used auto siphons quite a bit for that purpose

OK I think I have finally made auto siphons easy, having tried coiled hoses and other slightly complicated plumbing adventures, this has been the simplest and best I have come up with.

ADVANTAGES:
* No air tubes being required
* Small restricted water intakes such as in Bell siphons that could block are up are also not needed so any feathers/stones can flow straight through.
* Simple design with with no machining required and all components just pushed together.
* Complete emptying of growbed no puddle left behind

The drainage system begins with standard 40mm drainage fittings plumbed up to near my duckpond then adapted to 40mm pressure pipe fittings and final outlet pipes of both 15mm and 20mm both work perfectly well, although one would assume the smaller is more responsive.

The 40mm adjustable joining piece (the "fat" fitting) has a 100mm range which is adequate for most fine tuning. I set my highest height to have the top bend in line with the growbed media.
While the adjustable piece could be done away with in makes installation quicker and has helped the seeds scattered around the top germinate so in the next week I can lower the water to avoid algae growth quickly and easily

A decent video about bell siphons. Did any of you fine folk make this clip?

http://www.youtube.com/watch?v=t6mBjY7qsaQ

OK I'm confused... in that clip he says the air vent is NOT to create an air lock and stop the water flow. What pray tell is it for then? Airation? Do my bell siphons (still a figment of my imagination) not need this air vent then?

Hi NewAge, the bloke was/is a member here, that is his 2nd attempt at the video

...didn't catch his exact words Kuda, but he did explain the air vent doesn't stop/break the air lock, this is correct

...when the water level drops below the air tube, air is sucked in and mixes with the water flow (venturi style), the siphon action will continue until the water level drops below the Bell siphon cover and great gobs of air are sucked in, water flow through the siphon then ceases

...air is still being sucked into the bell housing via the air tube and seeing the water has stopped flowing, it wants to fall back down to its natural level, thus sucking more air through the air tube until the bell housing is again full of air

Howzat


...it would work better if he then had an outer cover to keep the gravel away from his bell siphon cover tho

so it is for aeration? I think I heard Bella had her breather removed. Logically I could never discern it's purpose. Les, how much aeration do you believe the breather hose provides? do you think it essential?