Backyard Aquaponics
A place to discuss aquaponics

Got a foodgrade 200L screwtop barrel today (was waiting for a while, but it was worth the wait...$24). It is going to be used as a header tank, and now i can really get into things......

just need to decide and figure out how to dump all that water as fast as possible......
Leaning towards a big bell autosyohon, was origionally thinking of a flout type thing in the middle of the tank, to give a larger useable volume (pivot closer to 180 degrees rather than 90ish), but bell syphon will prob be easier and more reliable...

bell siphon wouldn't need to be all THAT big I think i have a 90mm outer with a 40.mm inner i think............ dumps around 150 litres in under 10 seconds

thats the type of flow i am after and by big i ment tall, 870mm tall to be exact

You shouldn't have too much trouble getting it to siphon to very low in the barrel before it breaks, provided you build it right Dan.

i recon there would be some relation between the hight of the bell siphon and the required "drop" under it...............whaddayathink les?

If there is that will change my plans abit, could a larger water trap U help build up the air pressure in the syphon higher to give it a better "woosh"

Not quite right...the height of the u-bend (distance the air has to push out of the u-bend) determines how much higher the water rises above the bell siphon.

It depends on how deep the water is for the air to be forced out:
Pic 1 - it is < 5mm for the air to be pushed under (elbow was cut off )
Pic 2 - ~30mm therefore more pressure needed to force the air out, hence more water above the siphon...so keep the depth as low as possible

hmmm.....Thanks Les

i won't be able to modify the fittings to decrease the ubend size, as it is going to be distributed to multiple gb's but i will keep it as small as poss, and i can always make the syphon shorter to hopefully accomidate for this and let the water rise higher above the top of it

Wow i didn't realise it had been so long since my last post in here. I am making progress slowly....and although i have passed other deadlines i have set for myself. I aim to have it finished within a year of this post being created......

any updates there?

Looks great so far

Photos would be nice

Are you still around daniel???