Hitting The Holy Grail - Affnan's Style

They say, getting alternating divided flow between growbeds is the Holy Grail of Aquaponics. So anyone that manage to get it done can be called a "Holy Man" :)

My experimenting with siphon just about over, its good. Never wanted to missed this opportunity, so I embark on a long quest to far far away places and end up in my backyard to try and achieve this. I dream a lot, thinking and rethinking to make it, once I have an idea I'll put it to paper and as below is my vision how a binary flow divider should be.

This flow divider make use of a "shuttle valve" that will divert alternately between 2 growbed. This shuttle valve is move by two diaphragm in turn triggered by siphon suction as water start to siphon out from the watered growbed. This suction move the shuttle valve which will cause water to be routed to the other "waiting" growbed until siphon started and the process repeated.

Sound easy, yes it should be easy.
I called it the "Binary Valve", and yes Aquaponics has gone digital. I have tried a proof of concept model it work, but more needed to be done to ensure trouble free operation. This Valve synchronise to a siphon. This valve don't need any special siphon to do, just an ordinary stand pipe bell siphon. Water cutting out not required to be done by the siphon, binary valve take care of it.

My trial, as follow. What you need are:
Two of this, to make the actuator diaphragm housing.
Or any of these plastic tub, like ice cream container will do nicely too.
Make a big hole on its cover, while another hand hold a camera.
Like so...
and another on its butt
like this, and put an aerator hose connector (or a tiny butt plug) in it. You can have it centred if you want, I drill on the thickest part still it cracked.
Put a 15mm or 1/2" tank fitting on the cover after the hole made. Cut off excess threaded part to ensure adequate clearance for the diaphragm later on.
2 pieces of plastic as diaphragm, these the best I could do for now. This is one item need improvement.
The plastic sheet should be install like above later after more item done on the binary valve.
A make shift shuttle valve, I need to make this better just like the one on the diagram or I could use rubber tap washer. That blue rod is a balloon stick, you can use anything similar.
Above how a shuttle should be, using a rubber tap washer on a rod. This shuttle valve is very critical component of this divider, it must be able to be move freely without much restriction. 
Should look like this after install, this is mid position, it should be extreme left or right.
Mount the 2 lid on this valve assembly, I ran out of Tees, so only 2 Tees use the other is a hole drilled on the pipe.
Mount the plastic sheets on the end of the balloon stick. I use rubber end cap here to hold the plastic. A small screw with 2 plastic disc sandwich the sheet would do.
The finished assembly, mounted on water inlet. The shuttle valve is not tight fit so lots of leak. This is proof of concept, a lot more work needs to be done to make this use able. Only 2 tees use, I ran out of tee. I'll make better ones and test again.
Shown above when the siphon triggered it will move the shuttle across to provide inflow to the other growbed.

How it work.

  • As siphon started, there will be suction created inside the bell, this suction is the muscle power for moving the shuttle.
  • Suction will cause diaphragm to expand pulling the balloon stick, repositioning the shuttle.
  • Shuttle will divert water to the "waiting" growbed.
  • "Waiting" growbed recieve water, once filled its siphon will flush, repeating the process as above and routing water back to the earlier growbed.
This alternate action is controlled by the siphon, so it will be in synchronise with siphon and do not need any external control.

Okay, the holy grail just about to be broken.... I could be a "Holy Man"..... :)


  1. Affnan,
    This sounds really promising! I really hope you get it to work!

    I've used the "spider valve" or aquaponics valve, and I have to say I was a bit disappointed in it. The one that I had was supposed to switch the flow between four different outlets. However, I found that it was very unreliable. First, it required a really strong pump to provide adequate flow. Then, I found that sometimes it would stick, and it would not switch from one outlet to the next. I had to redo my setup to take it out of the mix. It would switch when the pressure of the water was cut off ( by turning off the pump).

    Your design concept is far superior, as it doesn't depend on the pump size, only on an effective siphon.

    Good luck!

  2. I get it, I get it! But, wont the valve return to neutral once the siphon is broken?

  3. @Brian, thanks for the comment I'll work on it now. It was a spur of the moment earlier today so, I best get it done. I'm confident it will work.. touch wood. Refinement needed on shuttle valve and the diaphragm.

    @Rey, It won't return to neutral since there is no spring to pull it neutral. Water pressing on it will keep it in one position at a time, it will function like a flip flop, waiting for the next siphon to pull it across and wait there for the next.

    I'll try to make it better tomorrow, today many hardware stores close, so I just use what ever I have.

  4. I see those nice polycarbonate bottles as suitable housing for the diaphragm. I've never made any of the bell siphon so I don't know how much vacuum it has on the breather tubes, it looks to me that the washer in the T that acts as a flow selector will not be tight so that it can move easily. It may not even be necessary as water always chose the path of least resistance...hope it works for you!

  5. Mahfudz, Pet bottles don't have the surface area to effectively multiply the vacuum. I need a wide container to give this effect.

    The shuttle valve cannot be tight, it will be difficult to operate if it is. Some degree of water leak is allowed to ensure freedom of movement. I'm banking on self sealing properties of rubber tap washer to reduce the opposite path flow on this installation.

  6. Then a plastic cookie jar with screw tops may be just right for you Affnan, the ones they sell raya cookies in...Btw, apart from making a growbed fill up faster with selective flow pattern (which makes the flood and drain cycle faster) and the siphon easier to break, what is the purpose of having a selective flow? Is it to make it possible of using a smaller pump? Or is it beneficial to the plants? I'm still wondering...

  7. @Mahfudz, its for using less water in the tank to irrigate more growbed. The ratio of 1:1 now can be expanded to 1:2 because you only water one growbed at a time.

    Having this ratio also means your fish water is cleaner or more fish can be rear in the same volume of water.

    That's why, its call "Holy Grail" of Aquaponics, trying to achieve sequential irrigation on growbed.

    This is more difficult to achieve, making it reliable is the greatest challenge. Read the comment by Brian above, he had use the Aquaponics valve but still its unreliable.

  8. Mr. Affnan, correct me if i am wrong. from what you have said, my understanding is that by alternately irrigate the grow bed, it could expand the capability of the whole system to do the ammonia, nitrite & nitrate conversion.

    i can see that by doing this, you can have the perfect flow timing for each grow bed. better than dividing the water flow and irrigate all the grow beds at the same time but definitely slower phase.

    But still, i cannot see where are the relations, since when you alternately irrigate the grow beds, therefore only one of them will works a time.

    i am curious whether there are thing that i have oversee.

    Thank you.

  9. @Colourful,

    The Ammonia conversion takes time its not a single pass process, so having more growbed helps.

    In volume of water if more fish are kept, they will produce more Ammonia, these need to be converted to Nitrates, and these Nitrates need to be use. If not they could cause problem back to the fish.

    So ability to irrigate more growbed from this same volume of water means that more plants can be grown and take up the nitrates.

    Effectively, what we would achieve is more crop and fish for same volume of water as compare to system which is not irrigated alternately.

    As mention earlier, conversion don't happen in a single pass, its takes time for bacteria action to happen. So amount of gravel in this multiple bed will give more surface area for bacteria to do their job.

    Its a well known subject amongst the Aquapons trying to irrigate more for less water. That's the reason for me to try it.

  10. HI affnan great work you are doing pioneering the aquaponics with new designs and ideas.im just a begging in this field and would like your help my set up is 300 gal fish tank and 3 1 foot ibc grow bed i have seen the swivel siphon and want to make one for my set up but still need more info measurements , where i can get talapia fingerling in kl.

  11. hi again my name is mehanna ive posted the note above