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flienlow
09-05-2011, 10:15 PM
Forgive me if this has already been coverd 10000 times, but I cannot seem to keep my bell siphons from running continuously. When the siphon starts, you can see the water level drop rapidly, however, once it gets to the air holes it just gurgles and the siphon will not break.
I know this is not the issue.
1. the height of the stand pipe cap. tried caping just above the stand pipe, and have also left a 3" cap between top of stand pipe and cap. Doesnt matter.

2. the diameter of the stand pipe. I have used 1/2"PVC and 3/4" pVC. Each diameter will drain the bed faster that it is being filled.

The only thing I havent tried is to put and reducer(on inducer hower you look at it.) on the stand pipe to create the venturi effect per Annan's videos on youtube.

Suggestions?

urbanfarmer
09-06-2011, 04:43 AM
Reduce your flow into the grow bed and see what happens.

Try a bigger air pipe to break the siphon or did you not use one at all?

Change the configuration of how the pipes that exit the siphon are. Remove everything so it just "drops" straight down. Do you have elbow fittings?

A picture would help us help you. There are so many ways to mess it up I can't just magically give you an answer based on that little information. Thanks!

davidstcldfl
09-06-2011, 05:18 AM
EDIT: Opps....didn't see UF's post...still working on my coffee. :D

Hi flienlow, If your bell siphon doesn't stop draining, it could be, something as simple as the water comming 'in', is too fast. You could split the line coming to the media bed, and send some back to the fish tank. Which could help add some oxygen.
You mentioned, adding a reducer to the stand pipe (affnan style). Normally this helps to 'start' the siphon. From experience, I noticed, that this speeds up the 'draining' of the media bed. The extra speed, 'might' help break the siphon.
The other option, is to try adding a snorkel tube. It's just a small tube, that comes out of the side of the 'cap'. How far it goes towards the bottom of the bed, sets where the siphon breaks. Here's a pdf, that explains their use...
http://www.ctahr.hawaii.edu/oc/freepubs/pdf/BIO-10.pdf

Sorry, I was confused by what you described in #1....?

1. the height of the stand pipe cap. tried capping just above the stand pipe, and have also left a 3" cap between top of stand pipe and cap. Doesnt matter.

I'll just mention some stuff, which sounds like, you've already done or know....?
-If your using a 3/4 inch 'stand pipe', your 'cap pipe', should be twice the size, or 1 1/2 inch.
-The 'outside' bottom of the 'cap' should be at the height of the 'stand pipe'.

Good Luck ... :D

flienlow
09-06-2011, 07:59 AM
my stand pipe is 3/4" and the cap pipe is 1 1/2". I also have a 2" strainer pipe that surrounds that with 1/8" holes throughout to keep the hydroton out.
The drain from the grow bed is 3/4" (it is necked down to 1/2" as I am using a 3/4" bung fitting through the grow bed, but that is just a pvc adapter to thread into the bung fitting and accecpt 3/4 pipe.) The 3/4" drain goes down and hits a 90 (possible issue?) and then travels to a 2 1/2" "T". I am using the "T" with about 6 inches of 2 1/2" pipe on either side with holes drilled in it. The thought behind that was aeration for the fish, and not wanting to blash them with a 3/4" drain flow.

here is a picture of my system.
No Fun with Hydroton (http://www.diyaquaponics.com/forum/showthread.php?1133-No-Fun-with-Hydroton)

The 3 orange home depot buckets have been replaced with 1 large grow tray.
Possible fixes:
1. get rid of 90 degree (would need new diffuser solution)
2. 400 Gal/hour pump too much? divert some water back to fish tank with a aerator from fill?
3. investigate "tube" on cap pipe
4. inducer on standpipe.

This is the best I can come up with on your suggestions.
Thank you all

bsfman
09-06-2011, 08:07 AM
I'm no expert on bell siphons, but before doing any major drain reconfiguration or changing your pump input rate, you might try increasing the hole size at the bottom of your cover pipe so as to allow a bit more room to let air in to break the siphon at the end of the cycle. If that doesn't fix it, then you could try the more labor intensive suggestions.

flienlow
09-06-2011, 08:21 AM
from my experience, the hole size doest matter. The water dips to a certain level and stays there. I have 4- 3/4" holes on the cap pipe. More than enough.

But thank you for sharing! :)

urbanfarmer
09-06-2011, 09:55 AM
from my experience, the hole size doest matter. The water dips to a certain level and stays there. I have 4- 3/4" holes on the cap pipe. More than enough.

But thank you for sharing! :)
Of course it matters! Where the air holes are in relation to each other can have an effect too. Ideally, you want it configured in such a way that the maximum air gets introduced into the pipe at one time otherwise the force of the vacuum will pull more water and continue the siphon (not what you want). YouTube fluid mechanics. There are a lot of basic conceptual videos that will give you an idea of what you're doing.

I can't really see the bell siphon from your picture, but it looks like you have several feet of pipe after the bell siphon... LOL! Even if the siphon gets air in the force of the water siphon in the rest of the tube will keep the siphon going. That means the water flow is about right for this condition. You probably hear a "gurgle gurgle gurgle" sound but it keeps on truckin' right?

Get a better picture of your siphon. It's impossible to guess what you did based on your description. You probably want a T fitting near the top of that long tube so that it doesn't make a siphon, but even then you will have some force from the resulting pressure differences.

Good luck!

flienlow
09-06-2011, 01:01 PM
I can't really see the bell siphon from your picture, but it looks like you have several feet of pipe after the bell siphon... LOL!

Even if the siphon gets air in the force of the water siphon in the rest of the tube will keep the siphon going. That means the water flow is about right for this condition. Hummm...... :? I have seen videos where there have been long pipes after the siphon but they still stopped?

You probably hear a "gurgle gurgle gurgle" sound but it keeps on truckin' right? YEP! How'd you guess? :)

Good luck!
At any rate a picture is worth a 1000 words and I need to provide photos. I wonder if I need a larger diameter pipe after the siphon that will introduce more air, perhaps venting the drain pipe somehow, or maybe just getting rid of the elbow will do it. The force of the water comment made me think. Fluid dynamics is getting the best of me.

Thank you.

urbanfarmer
09-06-2011, 01:24 PM
Well, if that 3-4 foot pipe is connected to the bottom of the siphon without breaking the siphon when it first comes out, then the WHOLE PIPE is part of the siphon... and unless you designed it that way for a reason, that in itself will create problems... it's easily fixed, but IDK if that's what's going on or not... we'll wait for the pics :-D

badflash
09-06-2011, 03:11 PM
If the siphon won't stop it is like UF said. The air tube that goes from the top of the bell to the point you want it to stop is plugged up. Make sure it is clear. Once air is introduced at the top of the bell, it will stop. The tube need not be big. Mine are only 1/4" OD aquarium tubing and my bell is a 2" pipe and the stand pipe is 1". Here are some shots of mine:

http://i25.photobucket.com/albums/c70/badflash/Greenhouse/cover.jpg

http://i25.photobucket.com/albums/c70/badflash/Greenhouse/standpipe.jpg

flienlow
09-06-2011, 10:16 PM
I think the issues is that I have more inflow than outflow. When testing again without any media in the tank, I had a good siphon, but the siphon would not out pace the infill and reaches a steady state at half way. You will notice that my cap pipe is much taller than my stand pipe. I did not have time to shorten it tonight. Perhaps that may be working against me as well. Here are the requested pictures. I tore it apart but just stuck it back together for the pictures.

http://www.diyaquaponics.com/forum/attachment.php?attachmentid=4721&stc=1http://www.diyaquaponics.com/forum/attachment.php?attachmentid=4722&stc=1http://www.diyaquaponics.com/forum/attachment.php?attachmentid=4720&stc=1

davidstcldfl
09-07-2011, 02:45 AM
In your very first post in this thread, you wrote.....
2. the diameter of the stand pipe. I have used 1/2"PVC and 3/4" pVC. Each diameter will drain the bed faster that it is being filled.
Was this 'with' the media in the grow bed...?

Now your saying....

I think the issues is that I have more inflow than outflow. When testing again without any media in the tank, I had a good siphon, but the siphon would not out pace the infill and reaches a steady state at half way.

Try testing 'with' the media in the bed.
If you then have too much in-flow, you can split the line comming form the pump...and send it elsewhere. :)

urbanfarmer
09-07-2011, 05:17 AM
Yep, that'll do it!

When you get a chance take a shot of the pipes coming directly out of the bell siphon. I am still concerned that it is creating a very long siphon tube whereas you need to introduce a hole somewhere, maybe some additionally linked pipes, where air can get in freely at all times.

davidstcldfl
09-07-2011, 05:35 AM
When you get a chance take a shot of the pipes coming directly out of the bell siphon. I am still concerned that it is creating a very long siphon tube whereas you need to introduce a hole somewhere, maybe some additionally linked pipes, where air can get in freely at all times.

UF....look at the pictures at the top of this page. The 'top picture' shows the lower section of the siphon drain, See the bottom of the metal shelf, at the top of the same picture?........ his buckets(grow beds) are sitting on it.
Here's an overall picture of his system....
No Fun with Hydroton (http://www.diyaquaponics.com/forum/showthread.php?1133-No-Fun-with-Hydroton)

I'm 'guessing' the 'down' part of the drain is just over a foot...(?)

stucco
09-07-2011, 05:39 AM
It’s hard to tell from the photo but it looks like your bell is way too long. I’ve had problems with this before using the same bells with my 14”and 12” beds. The extra two inches made a difference. I try and keep only about 3/8 of an inch between the top of the stand pipe and the bell.
Where you have the 90 on your discharge pipe mat be a bit short. Try adding enough pipe to get a slight upward angle as it connects to your 2 1/2” t.

urbanfarmer
09-07-2011, 06:04 AM
When you get a chance take a shot of the pipes coming directly out of the bell siphon. I am still concerned that it is creating a very long siphon tube whereas you need to introduce a hole somewhere, maybe some additionally linked pipes, where air can get in freely at all times.

UF....look at the pictures at the top of this page. The 'top picture' shows the lower section of the siphon drain, See the bottom of the metal shelf, at the top of the same picture?........ his buckets(grow beds) are sitting on it.
Here's an overall picture of his system....
No Fun with Hydroton (http://www.diyaquaponics.com/forum/showthread.php?1133-No-Fun-with-Hydroton)

I'm 'guessing' the 'down' part of the drain is just over a foot...(?)
Okay, I guess I was confused. I thought the bell siphon was in the top blue tub.. in which case these pictures don't really give you the whole picture! :lol: A foot is still too much, but I was thinking the down part of the drain was 3 or 4 feet!!!

So the bell siphon is in one of the orange buckets not the top blue one??? Anyway, I just want to see the WHOLE plumbing from the exit of the bell siphon to where it exits into the fish tank IN DETAIL. Otherwise, I can't say for sure, but again it looks like it's too long as stucco has also stated.

flienlow
09-07-2011, 08:42 AM
In your very first post in this thread, you wrote.....
2. the diameter of the stand pipe. I have used 1/2"PVC and 3/4" pVC. Each diameter will drain the bed faster that it is being filled.
Was this 'with' the media in the grow bed...?

Now your saying....

I think the issues is that I have more inflow than outflow. When testing again without any media in the tank, I had a good siphon, but the siphon would not out pace the infill and reaches a steady state at half way.

Try testing 'with' the media in the bed.
If you then have too much in-flow, you can split the line comming form the pump...and send it elsewhere. :)


Yes that was with media in the bed, and also when I was using 5 gal buckets. This should work without splitting the flow if I have a great outflow that inflow correct? I would like to to keep this the same for ease and simplicity.

flienlow
09-07-2011, 08:58 AM
Sorry guys-

These pictures got reversed. The bottom picture is the black grow bin with the siphon and me holding the 3/4" to 1" flange that I got for it along with the 1 1/2" cap pipeand 2" strainer.

The middle picture is just to show the diffuser that I made with 2" pipe.

The top pictures show the 3/4' inch pipe that is about 18" long connected to my diffusers setup for the grow bed just out of the picuture. I did it like this to break up the water flow for the fish and to aerate the water.

I removed the diffuser and just used the 3/4" X 18" drain pipe without media and it still kept a constant flow. Tonight I pull all stops and go whole hog with a 1" drain setup. If that doesnt work, I am going to burn all of this stuff and take up something less frustrating like Golf :)

davidstcldfl
09-07-2011, 03:57 PM
If that doesnt work, I am going to burn all of this stuff and take up something less frustrating like Golf

Maybe you'd like to buy a couple Penn reels on Ugly Sticks that I don't use anymore, now that I can just stick a net in my own fish tank and pull out 5 or 6 at a time.... :P :lol:

Hang in there....you'll get it... 8-)

flienlow
09-08-2011, 10:10 AM
Well I changed everything over to 1" pipe. I had a few issues where the gap between the siphon and stand pipe was restricting the flow, but have that sorted now. She drains really well. Tonight I will silicone the screen pipe to the grow tub, and fill it with media tomorrow. I also need to change my diffuser as we spilled a lot of water on the floor.

Still pending final test.

Just a little good clean fun with fluid dynamics :)

davidstcldfl
09-08-2011, 06:53 PM
Just a little good clean fun with fluid dynamics :)


So....you don't want to buy the rods and reels ? I was going to toss in my favorite beetle spins too... :P :lol: :lol:

flienlow
09-08-2011, 10:13 PM
Just a little good clean fun with fluid dynamics :)


So....you don't want to buy the rods and reels ? I was going to toss in my favorite beetle spins too... :P :lol: :lol:

Not quite yet, but I'll keep you in mind :lol:

urbanfarmer
09-09-2011, 07:10 AM
Well I changed everything over to 1" pipe. I had a few issues where the gap between the siphon and stand pipe was restricting the flow, but have that sorted now. She drains really well. Tonight I will silicone the screen pipe to the grow tub, and fill it with media tomorrow. I also need to change my diffuser as we spilled a lot of water on the floor.

Still pending final test.

Just a little good clean fun with fluid dynamics :)
Just to reiterate since I can't completely see what's going on from the bell siphon to the fish tank... make sure there is some added pipe in such a way that it does not allow the "exit pipe" to create a siphon all the way from the grow bed to the fish tank.

davidstcldfl
06-17-2013, 09:23 AM
Affnan style bell siphons seem to be the most reliable. A quick search will turn up lots of great info by him.... ;)

JCO
07-21-2013, 08:52 PM
A few pieces of straight PVC and 2 90 degree elbows makes a great siphon :mrgreen:

Apollo
09-04-2013, 04:27 AM
Flienlow and anyone else trying to use a Bell Siphon, I came so close to filling in my AP set up that I spent months building in the ground out of blocks and cement. I spent 3 week trying to get the Bell Siphon to work, before going to my own design. It's been working non-stop since Sept. ( No tweaking, adjusting, nothing ). Not sure why so many people keep pushing the Bell Siphon with all the problems that comes with it.

Check out my post, Pipe Siphon by Apollo

I made a mental note of this sign when I was attempting to get the Bell Siphon to work!
I HAVE NOT FAILED. I'VE JUST FOUND 10,000 WAYS THAT WON'T WORK. Thomas A Edison

Gilraen
11-07-2019, 10:42 AM
I am using a 3d printed bell siphon 5054 Does humidity have any affect to how it's supposed to work? It works great for 2 or 3 days, but then it can't seem to break the flow. I've tried reducing the flow, it won't start. I increase flow, it won't break? Would a stone guard help? Any suggestions?

Apollo
01-01-2020, 01:44 PM
Flienlow and anyone else trying to use a Bell Siphon, I came so close to filling in my AP set up that I spent months building in the ground out of blocks and cement. I spent 3 week trying to get the Bell Siphon to work, before going to my own design. It's been working non-stop since Sept. ( No tweaking, adjusting, nothing ). Not sure why so many people keep pushing the Bell Siphon with all the problems that comes with it.

Check out my post, Pipe Siphon by Apollo

I made a mental note of this sign when I was attempting to get the Bell Siphon to work!
I HAVE NOT FAILED. I'VE JUST FOUND 10,000 WAYS THAT WON'T WORK. Thomas A Edison

I was wondering if you ever got your system up and running?