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Pumping air through a flooded gravel grow bed

Discussion in 'General Aquaponics discussion - Aquaponics system ' started by Kachok, Dec 26, 2011.

  1. Jens UK

    Jens UK New Member

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    is there a wicking bed forum anyone can recommend?
     
  2. Kachok

    Kachok New Member

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    I am not wantng to build a wicking bed system though you might consider this to be some knd of hybrid. Think a 6ft (2m) wide gravel dam with a low intensity grid aireation system underneath it. Current flowing throgh it would be very slow given its huge surface area, on the grow bed side of th dam there would be a finer mesh mat filter to caprure the ultra fine solids that might have passed through the gravel. The fish tank end of the raceway would have a deeper sump end to allow easy removal and processing of the heavier solids. The far end of the raceway would be a much more shallow DWC grow bed with it's own gid aireation system. This entire system will be built in ground with a plastic liner, this should dramatcly cut construction costs since it does not require any custom fiberglass tanks and plumbing is kept to a minimum. The in ground setup should also help with the thermal stability which is a cheif concern here.
    I am still working on tweeks but I think the basis is pretty solid. I am calculating the costs in building a flood and drain platform over the fish tank, that would shade the fish and provide nutrifacation of the sump water not to mention a health dose of biofiltation, it seems a no brainer but it would raise the construction costs quite a bit since those 300mm deep gravel beds weigh alot and would require robust construction.
     
  3. Gratilla

    Gratilla Member

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    Wicking bed forums? Not that I'm aware of, although WBs are featured on a number of gardening forums. I'd suggest you start with these sites:

    http://wickingbed.com/
    http://www.waterright.com.au/

    And D/L wicking_bed_technology.pdf from the latter. That should give you a jump start.
     
  4. Gratilla

    Gratilla Member

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    Fine... but if you read msg #13 slowly, you will see that my response FWIW was to a number of underlined preferences specified in the OP's original msg.

    Nonsense. What you have also been known to say is:
    1) You know of no successful purely AP operations.
    2) One AP company has recently terminated operations.
    3) AP businesses can only succeed if they can generate income from other sources such as consulting, equipment sales, etc.

    Huh? You opened up the reference to the previous ("Dudley") thread in which I quoted Laulanie and Harris? And how many eminent supporters of your assumption have you quoted? Err, exactly none. :(

    And what you have also told us is:
    1) Long roots are an indication that the plant is in less than optimal conditions, sending out roots in search of additional nutrients, etc.
    2) White roots are an indication of effective solids removal.
    So jumping to "perfectly healthy" doesn't really compute, does it.

    What I said was that "fish are [entirely] optional". In addition, WBs don't suffer from having to be tightly coupled to the aquaculture side for success.

    Thank you.

    Your "Plant roots can be optimally oxygenated while inundated." is an assumption; my "Plant roots cannot be optimally oxygenated while inundated." is a theory. [Additional theories are: 1) AP plants have a higher water content than non-AP, 2) AP plants have lower nutritional value than non-AP. Neither of which are of any concern to commercial AP operations.]

    If you really really want to challenge my main theory, then ask your research org to examine root sections under a microscope for existence of aerenchyma tissue, physical proof of hypoxia. I have invited you to do so a number of times now. I can understand your reluctance to go this obvious route. If I'm wrong, the world will still rotate. If you're wrong <gasp>, your whole AP world collapses and all you are left with is ... a pair of frilly pink knickers.
     
  5. Kachok

    Kachok New Member

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    Anyone know a good formula for biofilter surface area/kg (lbs) of fish? I am thinking my design should have plenty, but I would like to make sure before I break ground.
     
  6. MattySEQ

    MattySEQ New Member

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  7. RupertofOZ

    RupertofOZ New Member

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    But you completely ignore the context of the posters thread... that he was looking at aquaponics methodologies.. a point I clearly made, and which you even include in your "quoted" response...


    And your point is?????.... and what I actually said.. was that there are very few successful "pure" commercial AP operations... two of which were until recently in Australia... one was recently closed as the owner is now consulting and building systems in Vietnam....


    Complete bollocks Gratilla... if you enter "Laulanie and Harris" into the search engine of the forum.. (choose "show posts")...

    The only references found are contained in this thread... where you "claim" to have mentioned them previously...


    Huh???... well the first point related to plant root growth in less than optimal conditions in soil... and the second point related to both hydroponic and aquaponic systems...

    Both are demonstrable facts.... even if you choose to ignore them...


    A "theory" is an untested "assumption"....

    The test of whether or not "plant roots can be optimally oxygenated while inundated".... or "can't be optimally oxygenated while inundated"...

    Can, and has been tested... by thousands of aquaponic, and hydroponic practioners... and even your originally quoted "SDI rice trials".. which you totally mis-interpret... and mis-construe into an "assumption" of your own regarding oxygen uptake... clearly shows YOUR "assumption"... to be wrong...

    As to your assumption... an untested "theory"... that

    Then please link us to any studies that show this to be the case... as I'm sure they would be not only be of "concern to commercial AP operations"... but to the tens of thousands of backyard aquaponic growers...


    I don't know if they have the funding, facilites or expertise to do so Gratilla ... but I'll happily do so Gratilla... and I'll forward a similar enquiry to those who have done substantial academic research with regard to aquaponics... like Dr Racocky at UVI, Dr. Nick Savidov in Alberta Canada, and Wilson Lennard here in Australia...

    Perhaps you could also find answers from the works of Dr. Mark McMurtry et al. at the New Alchemy Institute... or Rebecca L. Nelson and John S. Pade, or the Speranos....

    You claim to have compared wicking beds and aquaponics by your own personal experience...

    So ante up Gratilla... and show us the pictures of your trials... and research results....

    And show us links to the many commercial wicking bed operations that you claim to have some "personal" knowledge of...

    So far the only link you have posted regarding "wicking beds"... points to a forum where one member makes the point that "because they are low tech and DIY, there is no money in wicking beds so they are not promoted by industry".... which hardly proves the effectiveness of wicking beds... (which I don't doubt).... but doesn't disprove the effectiveness of aquaponics...

    Nor does it prove your assumptions related to oxygen uptake from the atmosphere by plant roots totally exposed to the air...

    Indeed the post on the same forum immediately above... suggests wicking beds (in this case referencing drippers) ...

    Just as in the SDI link you previously posted... the requirement for constant moisture...

    Likewise...aquaponics systems... "provide continuous optimum soil moisture."


    If you wish to dismiss aquaponics Gratilla... fine... you have already discovered a wicking bed forum that should provide you with gratification...

    And if the forum also allows for your indulgence, and your interest in cross dressing ... or womans underwear... I'm happy for you...:D
    .
    .
     
    Last edited: Dec 28, 2011
  8. Kachok

    Kachok New Member

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    Thanks for the calculator, turns out my ratios were darn near ideal, though I was going way overboard on the biofilter material. I was planning on using 10 cu meters, turns out I only need half of that even at a 2% fish mass daily feeding rate.
     
  9. RupertofOZ

    RupertofOZ New Member

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    Having more wont hurt Kachok....
     
  10. Kachok

    Kachok New Member

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    Too true, I was planning on using at leased 50% over the minimum volume anyway because you simply cannot have too much filtration, especaly if I can grow somthing in my biofilter dam so it is not wasted space. I am thinking that with enough aireation in front of the dam I can get some worm action and growth out of the gravel even if it is not a flood and drain. If my math is correct I can run a 500 sq meter growbed for my pilot system on only a 20,000 to 30,000 lph pump depending on how much growth I wanted to get out of the fish. It is that very low pumping requirement combined with the remarkable ease of construction that attracts me to the flow through style aquaponics.
     
  11. Jens UK

    Jens UK New Member

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    500sq meters growbed / 30000lph pump......wow massive system....
     
  12. Kachok

    Kachok New Member

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    Not really, real commercial systems I have seen are much larger, it is a pilot program to test the possability of going full commercial, and I might scale it down depending on what my reserch turns up. I want to be able to grown enough to make it worth my time to sell the porduce, but not so much that I would have to hire a staff for the opporation. Just me and my partner would be running the opporation to keep costs down to a minimum.
     
  13. Gratilla

    Gratilla Member

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    I also did the same search. My results:
    Harris: 17 hits, 11 relevant, 6 Gratilla, 5 RupertofOz.
    Laulanie/Lalaunie: 9 hits, 9 relevant, 5 Gratilla, 4 RupertofOz.

    Most of these were in recent discussions with yourself! So what is it, Rupert? "Complete Bollocks", low blood sugar or senile dementia?

    I'll look forward to your results. <Not holding my breath.>

    You want "complete bollocks"? Then the above quote attributed to myself is "complete bollocks". This is NOT what I said. To manufacture a quote and forge attribution shows desperation and is dishonest. Show us where I made this statement.
     
  14. Murray

    Murray Site Admin Staff Member

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    It would appear that this thread started by Kachok has been hijacked by others. Some of the more recent posts that are not really on topic have become very personal.
    Please desist.
     
  15. Gratilla

    Gratilla Member

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    Thank you. Rupert, however, does need to answer for his dishonest fabrication of quotations, either here or elsewhere. Clearly, he has nothing substantive to contribute on physical evidence (or lack) of hypoxia, water content and nutritional value of AP plants.
     
  16. RupertofOZ

    RupertofOZ New Member

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    I'll extend an apology in that regard Gratilla... I read your quote as referencing work by "Laulanie and Harris".... assuming it to be a paper by joint authors... when you were quoting both as seperate authors...


    Re : my comment regarding your "building both"...
    Well you did actually... here... http://www.aquaponics.net.au/forum/showpost.php?p=43119&postcount=13

    Sorry I didn't "cut & paste" the exact wording you used... "designed" rather than "built".... but they mean the same thing...

    Anyway, as Murray has pointed out... this thread has been hijacked away from the intentions of the poster... who was quite specific in his enquiry...
     
    Last edited: Dec 29, 2011
  17. Kachok

    Kachok New Member

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    I am having a hard time finding usefull sources of information on FloMedia aquaponics, do you have any sugestions on how to get the proportions correct? Right now I am planning on a 60 cu m fish pond flowing through aprox 10 cu meters of gravel, then through a thin finer mesh media, into an aprox 320 sq meter dwc pond (depending on the crop I choose as my primary).
    Water flow between 20,000 and 30,000 lph
    Feeding at 1.5% of fish body mass daily @40% protine
    Aprox 15kg fish meter cu (900kg total)
    Still working on the figures for aireation pumps (any sugestions?)
    This should give me about 5,000 holes in my DWC bed, plenty enough for my pilot program.
     
  18. jakesebastin

    jakesebastin Guest

    Very good information here regarding the Pumping air through a flooded gravel grow bed. generally the grow beds are good for the plants and is one of the necessary elements in the growing of the plants.
     
  19. Kachok

    Kachok New Member

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    I still have not found any reliable information on such a system, I am very well aware that the flood and drain growbed/biofilter is "better" at breaking down solid waste, thanks to the built in aeration, but seeing as it would be a HUGE expense to build the structure at that scale I am thinking a "flow through" system would be more financial feasible seeing as it requires no elevated stracture or custom built valves/timers. The ideal aquaponic system is quite the engineering project, especially if you are trying to design it around hardware store level supplies, and DIY structure, this has become something of an obsession for me. I would assume that gravel would still support nutrifacation and the breaking down of ammonia into nitrate even at a constant hight if it had enough O2 but there could still be another factor that I am missing somewhere.
     
  20. RupertofOZ

    RupertofOZ New Member

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    Kachok... I doubt that Murray would be prepared to provide any great level of detail of his "flomedia" system... although he has alluded that a complete breakdown will be provided in a forthcoming DVD...

    Don't get too hung up up the the "brandname" of "flomedia" though.... as posted... it's just a hybrid combination of media filled grow beds... and DWC raft beds... or NFT...

    Albeit... Murray may have certain "flow" parameters designed into his systems...
     

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