Messing around with Bell Siphons and Venturi aerators.

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threatco

threatco

Hey folks,

I wanted to share with you all the results of me testing some Bell Siphons and Venturi aerators for small scale hydro systems.

My inspiration came from watching this guy Rob's aquaponics youtube channel. Figure I will give him a shout out. Made for an entertaining and educational binge watch.


So my goal here was to see how practical bell siphons could be in the style of ebb and flow I do which uses under the bed totes. And also to see what was the deal with Venturi aerators and if they could be used practically.

This was all just using stuff I had on hand. I didn't want to run to the store to get anything, and I don't have much stuff. I also have some "extra" clones leftover that I have no other purpose for right now besides running experiments on.

I am also interested to see how their growth compares to their more tenderly treated sister clones in the 4 tote setup pictured further below.

Normally I would fill these totes up with grow media, attach a 1/2 and a 3/4 ID hose, throw the pump on a timer, and away I go. Standard ebb and flow stuff.

Now with this setup, I have 6 plants in net pots, sitting in cut out holes in the lid DWC style. I still have 2 holes in the bottom, but 1 is 3/4 ID hose with a Venturi going from the pump to inlet. And an approx 2-inch outlet made of Twd 15g weed containers, open-ended on top, many drilled holes on the bottom. It has a cut-out bottom of a large salsa container, with teeth cut out around the base, acting as the bell-siphon over top of that. The tote lid holds it in place.

experiment.png


So while messing around with this general design, I encountered difficulty in getting the bell-siphon to "burp" all the way down.

As you will see in the time-lapse video, what most often would occur is there would be some burping, enough the allow some air into the bell. But then the pressure would stabilize and it would just siphon out exactly as much water as was going in. Keeping the level unmoving in the low position.

I don't know why this is exactly. As shown in the time-lapse video, even when I lower the power from 100% to 10%, the lower flow rate is not enough to make it "burp" down and reset.

The only thing that reliably makes it quickly cycle from flood to drain is using the "wave" setting on the pump, which makes it turn on and off at a set rhythm. This makes enough wave action in the tote to trigger the final burp and cycle the system.

So the question becomes, what variable most needs to be tweaked in order to successfully run the pump at 100% without wave setting, and have the system successfully cycle up and down.

Should I make the teeth at the base of the bell-siphon bigger? Different shape?

Does the bell-siphon need to be wider? Taller or shorter?

Is the relatively low "height" of the outlet too low to make it work with that wide of an opening?

Something else?

I will keep experimenting with it.

If I end up keeping the system going I will block out the light somehow so I don't have an algae farm on my hands.


Inked20200520_215255_LI.jpg
 
stoneyluv

stoneyluv

That is a very cool venturi!!! wow that is a lot of oxy in there!!!!

I've made a few bell siphons myself for my aquaponics and have tried a few varieties and pretty much had success with all of them. it's all about the balance of pressures and that comes from sizes of tubes and bells.

what does your inside down tube look like? ( a photo without the bell on)... how much distance between the top of the down tube and the inside of the bell?

and lastly what is the OD of the down tube and the ID of the bell?

so when you are using your desired flow rate, how close is it from burping, is it right in the edge? or is it not really close to burping at all?
 
threatco

threatco

That is a very cool venturi!!! wow that is a lot of oxy in there!!!!

I've made a few bell siphons myself for my aquaponics and have tried a few varieties and pretty much had success with all of them. it's all about the balance of pressures and that comes from sizes of tubes and bells.

what does your inside down tube look like? ( a photo without the bell on)... how much distance between the top of the down tube and the inside of the bell?

and lastly what is the OD of the down tube and the ID of the bell?

so when you are using your desired flow rate, how close is it from burping, is it right in the edge? or is it not really close to burping at all?

The downtube is 3 inches tall. 2.5 inches wide. It restricts at the "bulkhead" to I think 2 inches. And the drain has holes to simulate an elbow that most systems use by further restricting flow.

The bell is a little more than 5 inches tall but has a concave top that caves in about 1 inch. Making the avg height inside about 4 inches. (got to love weird variables eh?)

The bell is 4 inches wide.

All the plastic is <3 mm thick. So almost the same ID as OD.

I had a few different versions before this one and I have been closer to getting a full burp on those.

This one drains fast, then burps partially, then the water inside the bell lowers to level out with the top of the downpipe, while the tote's water level stays just barely over the top of the bell's teeth level. When in this situation it just stays like that and maintains the same level indefinitely. Would take my making a wave or splash to get it to cycle.


Inked20200527_015810_LI.jpg


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stoneyluv

stoneyluv

your real close man, it would try a few things..

first try, i would find a piece of rubber tubing preferably like 3/8" id or bigger, and attach it to the side of your bell holding it with ties or bands.. insert the tube into the top side wall of the bell, make sure you drill the hole small and shove the tube tightly into it creating a seal. sometimes it helps if you cut the end of the tube on an angle at least i have found it helps me.. and then cut the bottom of the tube so it matches the same height as your cutouts on the bottom of the bell. this will allow the bell to get an extra gulp of air when it reaches the bottom end of the tube. but really you can use anything even something rigid like a pen tube or marker tube... use stuff you have laying around if ya can.. as long as you can get it to seal to the bell you can use it.... hot glue guns and rtv work great too!!

Inked20200527_015810_LI.jpg


if that doesn't work then i would flare out the top opening of the down tube and make the water swirl as it goes in. the turbulence helps gulp a little extra air in, this method usually works good when sometimes it burbs and sometimes it doesn't kind of close..

and the last and final try would be to try a different bell...those side ridges could be trapping small amounts of air and that would keep it from getting that solid big gulp of air, the ridges might buffer that gulp and give less air over a longer period of time versus one big sharp gulp of air... not sure if that makes sense but it did in my stoned mind... hahaha

best of luck man, i would love to hear how it goes and how you fixed it!!!
 
threatco

threatco

I'm going to try popping a 1/2 inch tubing elbow connector into the spot you suggested on the Bell and put a ~3 inch long 1/2 ID tube going from that to the teeth line and see how that goes.

Will report back shortly.
 
stoneyluv

stoneyluv

also the diameter of your downtube is kinda big. for that size you could get away with an inch ID. maybe try to stick a smaller pipe inside that one and seal it to the bottom with glue or epoxy..
I've used this stuff for years and always keep a tube on hand... it seals and glues and fish safe!!!!

DSCN1390.JPG


best of luck!!
 
threatco

threatco

Think I have it dialed in!

At first with the hose near the bubbles, the siphon would initiate slower than normal, and the final burp to stop the siphon would not happen. Even when the hose opening was put fairly high by adjusting the angle of the elbow.

But on the other side, it not only worked when positioned at a higher level, it also worked when I positioned it fairly close to teeth level. And worked quickly too. About a 43-second drain phase plus a 32-second flood phase.

Why did it work on one side but not the other? Bubbles? Who knows...🤷‍♂️


I had an ID 1.5-inch drain at the bulkhead before expanding it, but it could not keep up with the input from the 2641 GPH pump, even with the 3/4 hose and the venturi restricting it, regardless of there being a bell or not. This is some serious overkill on the pump strength to grow-bed size ratio.

When I had the smaller drain size, I was able to get the Bell Siphon to work, but just not at 100% power on the pump.

Super appreciate the help!

Any other tips or ideas are most welcome.

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Time-lapse videos are 30x speed.
 
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threatco

threatco

I negotiated a temporary home for the six ladies in this experiment. Will keep them here a couple weeks until they grow against the wall, then will play it by ear. Gave them a cpu cooling fan to circulate air around in there to keep them squirming.
 
threatco

threatco

@SPARECHANGE

Clones took at same time as my closet you've seen. Amazing how big of a difference a little stunting makes.

This one Hunchback of Notredame girl self-trained her self like that in response to low light from an 18w "grow" light.

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SPARECHANGE

SPARECHANGE

and that's ebbnflow?
amazing diy innovation
no algae issues from light penetration?
u could go deeper on the hydroton
my netpots were supposed to arrive with coco jackets n covers.
they fuct me
if i don't line the netpots/hydroton, with homemade, coco jackets- the seedlings drown/damp off. might give u ideas. I'm absolute shit in ummm... rockwool cause i can't perceive moisture lvl n fuk it up, religiously.
when the seedlings r poorly rooted, or not beyond the grow plugs... i basically have to bury em deeep deep in the netpots n go easy, if at all on coco floor... just scizzoring up one of those hippie, hangable coco planterz that are reminiscent of 60s, corkboard walls. if the roots, especially clones, are 6" deep... i can take the phalic shaft, to hydroton top lvl n just bury the 6" roots, lower... having a bigger start n bigger tuna can style, shaft/trunk... i can tell in first two wks/spurt, a rough weight estimate, upon completion.

I'm just kinda brainstormin, the less obvious points for u to dissect n c if any one thing, may b of use n your fellow infidel, salt system. keep it on the lowdown... people get banned, for less. the fewer who know.... the more time they'll let us snipe their brighter methods, before the jig is up n they run us off by fork n flame!
 
SPARECHANGE

SPARECHANGE

u ever go seeking new delay methods... I'm pretty sure I've inadvertently discovered them all, bitching about trimming four tanks, all at once... well... listening to my lovely g, bitching about it, anyway.
scrog?
 
SPARECHANGE

SPARECHANGE

imma catch up on ur thread

i like ur use of the term, "extra", clones... blessing and a curse, eh...
ok, so i c the algae i was wondering about... in an aquarium, green, is healthy.
is the algae a zealot, "purpose", or u battling it? light penetration... or... the guard ain't allowing it, in mine. could b either. no algae, of any color, visible, upon flip days... cept perhaps a light minimal brn coating, one wouldn't c, without scrubbing. probably, salt n shit vs algae buildup. there is a lil growth, on lids from moisture, in ones that go longer.
 
SPARECHANGE

SPARECHANGE

Hey folks,

I wanted to share with you all the results of me testing some Bell Siphons and Venturi aerators for small scale hydro systems.

My inspiration came from watching this guy Rob's aquaponics youtube channel. Figure I will give him a shout out. Made for an entertaining and educational binge watch.


So my goal here was to see how practical bell siphons could be in the style of ebb and flow I do which uses under the bed totes. And also to see what was the deal with Venturi aerators and if they could be used practically.

This was all just using stuff I had on hand. I didn't want to run to the store to get anything, and I don't have much stuff. I also have some "extra" clones leftover that I have no other purpose for right now besides running experiments on.

I am also interested to see how their growth compares to their more tenderly treated sister clones in the 4 tote setup pictured further below.

Normally I would fill these totes up with grow media, attach a 1/2 and a 3/4 ID hose, throw the pump on a timer, and away I go. Standard ebb and flow stuff.

Now with this setup, I have 6 plants in net pots, sitting in cut out holes in the lid DWC style. I still have 2 holes in the bottom, but 1 is 3/4 ID hose with a Venturi going from the pump to inlet. And an approx 2-inch outlet made of Twd 15g weed containers, open-ended on top, many drilled holes on the bottom. It has a cut-out bottom of a large salsa container, with teeth cut out around the base, acting as the bell-siphon over top of that. The tote lid holds it in place.

View attachment 978223

So while messing around with this general design, I encountered difficulty in getting the bell-siphon to "burp" all the way down.

As you will see in the time-lapse video, what most often would occur is there would be some burping, enough the allow some air into the bell. But then the pressure would stabilize and it would just siphon out exactly as much water as was going in. Keeping the level unmoving in the low position.

I don't know why this is exactly. As shown in the time-lapse video, even when I lower the power from 100% to 10%, the lower flow rate is not enough to make it "burp" down and reset.

The only thing that reliably makes it quickly cycle from flood to drain is using the "wave" setting on the pump, which makes it turn on and off at a set rhythm. This makes enough wave action in the tote to trigger the final burp and cycle the system.

So the question becomes, what variable most needs to be tweaked in order to successfully run the pump at 100% without wave setting, and have the system successfully cycle up and down.

Should I make the teeth at the base of the bell-siphon bigger? Different shape?

Does the bell-siphon need to be wider? Taller or shorter?

Is the relatively low "height" of the outlet too low to make it work with that wide of an opening?

Something else?

I will keep experimenting with it.

If I end up keeping the system going I will block out the light somehow so I don't have an algae farm on my hands.


View attachment 978224
insanity

dunno the pump

tech

and comprehend ebb n flow

not the mechanix of the systems, besides a pump n gravity feed systems, beyond.

so I'll shoot some pix of the head attachment of the cloning machine, which may give u ideas

and a pic... if i can dig one out...
of the gen hydro's, designs, for the hydro versions i converted and as to growth diff...
no better time than when my seedlings spurt... without the stretch... n btw, askin about strain, earlier... ur lookin at a combination of influences, to c the nothin but bud, gals. light overlapping of blurples n red... diox to 1500+... (bout 16avg), aero, manipulation/scrog n aero. qp per tank was original goal... it's ridiculous, now- 3/4lb-1lb per and i freak out; can't give it away, fast enough to feel comfortable, sleeping without a lil home protection/red rider... minus the eye... so... ur gonna enjoy the overlap n similar effects n there... with ur "extra"... clonez 😁. i keep wanting to snatch more, but know if i do... I'll b employing the previously mentioned stalling techniques, with annoying regularity.
 
SPARECHANGE

SPARECHANGE

your real close man, it would try a few things..

first try, i would find a piece of rubber tubing preferably like 3/8" id or bigger, and attach it to the side of your bell holding it with ties or bands.. insert the tube into the top side wall of the bell, make sure you drill the hole small and shove the tube tightly into it creating a seal. sometimes it helps if you cut the end of the tube on an angle at least i have found it helps me.. and then cut the bottom of the tube so it matches the same height as your cutouts on the bottom of the bell. this will allow the bell to get an extra gulp of air when it reaches the bottom end of the tube. but really you can use anything even something rigid like a pen tube or marker tube... use stuff you have laying around if ya can.. as long as you can get it to seal to the bell you can use it.... hot glue guns and rtv work great too!!

View attachment 978242

if that doesn't work then i would flare out the top opening of the down tube and make the water swirl as it goes in. the turbulence helps gulp a little extra air in, this method usually works good when sometimes it burbs and sometimes it doesn't kind of close..

and the last and final try would be to try a different bell...those side ridges could be trapping small amounts of air and that would keep it from getting that solid big gulp of air, the ridges might buffer that gulp and give less air over a longer period of time versus one big sharp gulp of air... not sure if that makes sense but it did in my stoned mind... hahaha

best of luck man, i would love to hear how it goes and how you fixed it!!!
I'd have to touch it
to learn it
not just read n c, but break it, with my own hands, but as i keep seeing, "burp"... r we talkin water, or air pressure and if so... and wave works with regularity, what about the weird dial timers, with more settings than common strip timerz? ok... then... how bout air???
the gen hydro sstm for hydro is a hollow vertical dowel, with 6 holes around top of "pole" and one, just below. they use 1/4", tubing, I'm estimating... from aquarium pump, at the individual, just below top hole and the 6... spider out, drippin to netpots, flow varied by pump settings n whatever timer, if any... can run through darkness; no problemo... and it causes a suction up from bottom of that @ 18" dowel, up the reservoir, etc... out the tipity top n the oxygenation that route, is netpots drippin, breaking surface tensions... i preferred additional stones n figured wtf... may as well insure atomized bubblez n spray, with the areo conversionz... sooo maybe more ideas. pumps=lotta powa... check valves= more opportunity for clumsy fat man to experiment... once... with electrocution. wasn't lookin to go that direction, though. so... I'll grab some pix. the only aholes i saw rivaling growth, etc... were the brix/zealot, hardcore methodists n they put in wayyyy too much work n personal offense (other fundamentalists on other, terrorist sites)... for results a lil investment was gonna cheat my ignorance... racing a clock, against my lovely g's, legit opioid, pain management n Walgreens sponsored, addiction.

there's like a horizontal crucifix

mounted on a typical aquarium water pump and the spray head replacements, come with every collar order.
u like em, i have plenty extra... address... next mo budget, no problem. seems like they'd b under a buck a handful, at a hardware store, in the pot aisle 😁.

so... if i pushed air in the dowel...
it'd vacuum n drip in 6"... no problem. maybe ur mental unraveling of the physics behind it... solve some of ur question marks. often, how i can still learn without knowing... wtf 😁.
 
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SPARECHANGE

SPARECHANGE

i could c u workin miracles, spending a weekend, cracked out with tweakers, tweakin a cloning machine, apart... staring at it... high off ur asses, playing paper scissors rock, for which one of your, "i can still fix it!"'s, will play out, first...
 
SPARECHANGE

SPARECHANGE

The downtube is 3 inches tall. 2.5 inches wide. It restricts at the "bulkhead" to I think 2 inches. And the drain has holes to simulate an elbow that most systems use by further restricting flow.

The bell is a little more than 5 inches tall but has a concave top that caves in about 1 inch. Making the avg height inside about 4 inches. (got to love weird variables eh?)

The bell is 4 inches wide.

All the plastic is <3 mm thick. So almost the same ID as OD.

I had a few different versions before this one and I have been closer to getting a full burp on those.

This one drains fast, then burps partially, then the water inside the bell lowers to level out with the top of the downpipe, while the tote's water level stays just barely over the top of the bell's teeth level. When in this situation it just stays like that and maintains the same level indefinitely. Would take my making a wave or splash to get it to cycle.


View attachment 978238

View attachment 978240

View attachment 978236
View attachment 978239
View attachment 978237
toilet valves burp similarly? the toidy n pool share similar, float shutoff valves... any help?
 
SPARECHANGE

SPARECHANGE

[round of applause]
all caught up

heart felt familiarity with, "i dunno wtf i did, but it's working, now... fuk it..."... lmfao

ingenious, man...! love that i got to c the end, without the suspense of the month! yup...: i cheated!
 
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