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Strider

Dual loop system build.

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So what is a dual loop system??

RAS aquaculture system & aquaponic system which can operate linked and independent??

I am I missing something where's the magic?

 

Phri, this involves a normal RAS operation, but the fish effluent solids are processed to fertilize a crop and fish effluent water is used for irrigating a crop. The crop system can be a soil field or a recirculating organic hydroponic system.

 

The crop effluent water never returns to the RAS operation.

 

Water exchange and systems are calculated so that there is zero water wasted.

 

 

The aquaponic system is designed for the aquaculture and horticulture to normally operate independent of each other.

 

 

Quite different from traditional aquaponic systems. Normal operation of traditional aquaponic systems were designed where the RAS and horticulture are operated dependent of each other.

Edited by crsublette (see edit history)

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Here is my advice: go to the source for the knowledge and follow his advice in detail. get access to all of the articles/calculators and help you may need to make it happen. That $149 is a ridiculously small amount in the big scheme of things. If you are too cheap to pay or whatever reason you may have, then maybe you should have built a chop2 system. Since this decoupled system is very complex the devil is in the details. I wouldn't have the knowledge I have today if it weren't for Paul and a few others that I feel that I can trust to get accurate answers from. These forums help indeed but when it comes to the complexity of these systems we need the whole picture. You won't get that since none of us has the very experience that the original designer of these systems has.

And if you strayed from the design and are not following the operating procedures you will get a different result.

Cheers

Ok, thanks. So your advice is to go ask paul. Got it.

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OK, so getting back to my problem ...  I was thinking of putting a couple of small Talapia in the IBC sump tank on the fish side to see if their ammonia and other waste may bring down the Ph.  I get a few babies that spring up in my RFF or MBBR and could just throw them in the sump. I would start out small with just 2-3 inchers and work up from there. What do you think?  

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I have noticed that some hydroponic operators have employed adding co2 gas to the water to acidify it.  I have no practical knowledge with it myself. Supposedly there is a controller that will add co2 till the ph reaches set point.   While it won't fix the need to add acid to the system , you may be able to automate it if you so desire.   They do seem pricey and hence why I gave up on dual loop at this time.

 

http://boards.cannabis.com/threads/using-co2-to-control-ph.59113/

 

 

A discussion of experiments/tinkering I found with google.   Maybe Rupe has heard of this or used it himself and can give insight.  I hope you find a practical solution... but if growth is going well, maybe the elevated pH is ok?

Now that is very interesting. I wonder if seltzer water would work or I could get that machine people buy to make their own soda and use it to infuse distilled water with CO2 and pour that into the tank?  Anything is better than acid.

 

Well growth is good but what I find is that some fruits are slow to grow or the flowers take an eternity to develop. That is to be expected in a nitrate rich media that is deficient of other minerals and essentials.  I once made a potassium spray and sprayed it on the leaves directly and it made quite an immediate difference. 

The other issue is my MT tank which is not offline (like most?) until I pour it into the plant sump. It is always circulating into the plant side sump and is empty with only a venturi for O2 injection. The fish solids are free floating in the MT. 

 

Oh, and don't forget my back is always hurting and my feet are sore from wearing combat boots for 30 years...lol  But I digress.

Edited by Strider (see edit history)

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Paul van der Werf is much like you, an experienced RAS aquaculture engineer. He is the guy trying to help hobbyists with this "dual loop" aquaponics idea, when he is not busy with his day job of engineering. :)

 

 

 

Yep, I will say one thing about Paul, he does grow some good looking stuff! His garden looks like the hanging gardens of Babylon...

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I am sure this has been on this forum before; Without taking away credit to anybody, but one of the farms here runs a dual loop system for at least 15 years: http://www.tailormadefishfarms.com.au

 

As far as I know, brain behind this is Prof Dr Rocky de Nys who is now at James Cook Uni in Townsville.

 

Rocky is another "Dutchy" like Paul and me too.

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Yep, I will say one thing about Paul, he does grow some good looking stuff! His garden looks like the hanging gardens of Babylon...

 

Hi,

 

For the record......Paul is a gifted aquaculture engineer, he produces the best system pipework that I've ever seen......and, yes, he may even "grow some good looking stuff."

 

But he's not here......he left of his own will......and he said that he's not coming back while I'm here....and I'm not planning to go anywhere just yet.....so it's unlikely that he'll be coming back any time soon.

 

While he has produced a good deal of useful information, he is not always accurate, he can be difficult to work with and his ideas are not essential in most cases and not even desirable in some situations.

 

Littering these threads with gratuitous homilies about Paul without including useful and factual information is distracting if not just plain irritating.  In fact, several members have described it as spamming.   Paul took full advantage of APHQ during the early years of building his business and, as he made quite clear, he has no need of us now........so it's time to stop the BS.

 

Charles and Mathias, it's time to move on......or move on.

 

I will delete every future reference to Paul or his business that is not accompanied by relevant useful information.  Similarly, I will remove all comment which is disruptive. 

 

If you have questions, comments or concerns about my direction, feel free to PM me........or the forum owner.  This matter will not be canvassed publicly on this forum.

 

Gary

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Hi Phri,

 

You're quite right......Tailormade Farms stands as the enduring example of commercial aquaponics in Australia and was "dual loop" (by design) long before the term was ever conceived.

 

I think it's time to take this discussion back to the fundamentals.  It's become far too convoluted.

 

Rather than hijacking Strider's thread (any more than has happened already), I have initiated another discussion on dual loop/open loop/decoupled systems.....where we'll begin by looking at the reasons why it might be done.....HERE.

 

Gary

Edited by Gary Donaldson (see edit history)

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You're quite right......Tailormade Farms stands as the enduring example of commercial aquaponics in Australia and was "dual loop" (by design) long before the term was ever conceived.

 

Nope.. Tailormade is NOT a "dual loop" configuration.. far from it.... it's actually a "run to waste" system...

 

Solids wastes from the screen filters are just dumped onto field crops.... and the NFT water runs to waste.... it is NOT recirculated...

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I understand that.  I regard it as dual/open loop or decoupled because fish and plant production are isolated from each other.  The water flows from the fish tanks to the plant side - never to return. 

 

The water that comes from the fish tanks is dosed to meet the specific needs of the plants being grown.

 

As you're aware, 'run-to-waste' is something of a misnomer, these days.  Effective system design means that minimal water is 'wasted' and even that small amount can  be put to plant production if the operators choose to do so.

 

In my view, the Tailormade Farms satisfies all of the broader reasons for de-coupling.....even if it's not compliant with some narrow definition imposed by vested interests.

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Phri, I appreciate your contributions with your aquaculture background so don't take what I said above the wrong way. It's not aimed at you at all (just in case that wasn't obvious) :)

No worries Mathias, I understand its not a reaction on my posts... and I am not going to give my opion on this as this will be not fuctional.

btw beside the aquaculture engineering things I am doing in the industry,  I am also teaching in an undergraduate course; including a subject on aquaponics.

Edited by Gary Donaldson (see edit history)

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Well it has been a while since my last update.  Sorry about that!  So, I have been trying different ways to filter my water.  I went with a felt sock type filter that worked well but required frequent cleaning; twice a day. The socks eventually degrade and need to be replaced. 

Then I went to a wedge wire / felt sock combination. That was OK but the socks still needed frequent cleaning and the wedge wire needed cleaning as well.  So still a daily chore.  Them I replaced the felt socks with a 74 micron basket. It fit into a 5 gal bucket.  Still a lot of daily cleaning (probably should have went with a 200 micron basket) as did the wedge wire. 

I placed a conical bottom on a 55 gal barrel and filled the barrel with river rock, 3/4 inch gravel, pea gravel, and topped it all off with chicken grit. (crushed granite).  While most of these so called birdman gravel and sand (G&S) filters feed water from the bottom working its way up and out the top into the sump tank, mine gets its water from the top and works its way down and out the bottom of the conical bottom into the sump.  It does have the customary backwash plumbing tgat uses a shop vac to dislodge the waste for cleaning. Cleaning is every three days.  So far I have observered several issues.  First, my drain is too small and needs to be increased to a 2 inch size.  My pump my be a bit much as well.  The pros are very clean water. Crystal clear! Also less frequent cleaning times. The con is it uses more water to clean the sand out.   But I can say that of all ways I have tried this is by far the best. I will work on a video to show it hopefully today! Cheers all! 

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lol.. its all good. those bag filters and sieve combo is a pain.. I thought i had mentioned that to you strider.. maybe it was someone else.. its all good though. your build is producing which is more than I can say about mine :(

its talking too long for me to get it going

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7 hours ago, swedeaquaponics said:

lol.. its all good. those bag filters and sieve combo is a pain.. I thought i had mentioned that to you strider.. maybe it was someone else.. its all good though. your build is producing which is more than I can say about mine :(

its talking too long for me to get it going

Why isn't your system producing? Hang in there buckaroo!  You are having a bad summer, first Bernie loses the primary and now this. Lol

 

Edited by Strider (see edit history)

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On 9/5/2016 at 10:43 PM, Strider said:

Why isn't your system producing? Hang in there buckaroo!  You are having a bad summer, first Bernie loses the primary and now this. Lol

 

LOL...It has been a rough summer indeed.

My system has been worked on very slowly and the heat of the summer has not allowed me to do anything. Now the nights are starting to cool off so it should drop water temps to reasonable levels. Then all I need is shade cloth and a cover for the raft and I will be off and going.. :) 

MT is kicking butt though. Ready to go ;)

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On 9/14/2016 at 8:20 PM, phri said:

Just came across a paper on dual loop systems.

See: http://www.int-res.com/articles/aei2015/7/q007p179.pdf

Always good to read up on original research

Excellent PDF. Validation is always good to read in hopes for clarification.

Don't know what else there is to be gleaned from it that would enhance current thinking by practitioners since the components and mechanisms involved in the document are quite rudimentary and actually practiced to this day by others... Nice to read validation that it works, has been compared to the results of other systems (including McMurtry's), and actual "scientific research is active and continuing" on the system idea. Thanks to the authors allowing the system idea to be capitalized upon, patented, and funding future research... Very interesting read.

Edited by crsublette (see edit history)

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On 9/14/2016 at 8:20 PM, phri said:

Just came across a paper on dual loop systems.

See: http://www.int-res.com/articles/aei2015/7/q007p179.pdf

Always good to read up on original research

Phri, as I think all consultants and small businessmen are aware, the marketing tactics utilized to promote one's services... and this applies to everyone equally... I have yet to encounter a doctorate nor consultant that has not utilized marketing tactics to their advantage, such as suggesting one's systems "can produce 20x of another" without evidence along with another saying "he has been the first to successfully employ a design on a quite large, commercial scale". I am just using the content available due to particular participants that "which won't be named" (lest the wrath employed by moderators).

I also find how this PDF proves the fact that McMurtry's work has not gone "unnoticed" nor avoided nor slandered to/by those whom matter in the industry to progress "sustainable food production", as his work was explicitly referenced in that PDF.

I wish we could move on to promote education rather than the contrast, as the mission should be of these type of forums, which the lower traffic from more recent times is any indication otherwise, unfortunately.

Nevertheless, the original research is quite interesting.

Edited by crsublette (see edit history)

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