Not another bloody aquaponic post....

Discussion in 'Planting, growing, nurturing Plants' started by earthbound, Nov 9, 2005.

  1. Veggie Boy

    Veggie Boy Junior Member

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    There are a couple of important considerations - which I'm sure Joel could give you the answer to.

    Firstly - in hydroponics, the surface area of the gravel acts as a home for the organisms/bacteria that are breaking down the nitrates and stuff. I don't know whether vermiculite would do the same.

    Secondly - I would think you could have problems with vermiculite clogging the system. In hydroponics this medium is normally in a pot or something which then has the water flooding past it, through the PVC pipe or whatever.

    As a final consideration - pea gravel is heaps cheaper and also I have heard that vermiculite can cause respiratory problems or even cancer if breathed in??
     
  2. earthbound

    earthbound Junior Member

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    Vermiculite will work, but it doesn't last well long term, perlite is probably a little better than vermiculite, but you have troubles with it breaking down as well. If weight is really an issue, then the best thing is hydroponic expanded clay, though it's expensive.

    Continuous flow is good, and two out of three of my systems are continuous flow, however, it's also more work and more pumping, it depends on specific situations. Personally for ease of use and less maintenance I prefer the flood and drain.
     
  3. frosty

    frosty Junior Member

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    what about that copra stuff they use in hydraponics ? I suppose it is expensive :roll:

    Phil also thought maybe blue metal :? I think probably not but why he proposed it is because there is a big pile up the road on the verge :evil: :lol: :lol:

    frosty
     
  4. snaggs

    snaggs Junior Member

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    Why is it more work? That aussie who did his PHD on it said that continuous flow was 20% better or something. It also means you dont need a flood system etc.

     
  5. earthbound

    earthbound Junior Member

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    Yep, I'm farmiliar with Wilsons work, though as I said, having both types of system, my PERSONAL preferance is with the flood and drain.

    In a continuous flow system the water flows in the same spot all of the time, and plant roots build up in the areas where the water flow is. As the plant roots grow and increase in size, they begin to change the flow of the water within the gravel. I've found that over time this can lead to flooding of some areas because the roots slow the flow of water through the gravel, and it can also lead to other areas of your gravel bed become dry due to blocked areas caused by root mass...

    With a flood and drain there ae no particular areas where the water is flowing all of the time, the whole bed fills up, then drains, so water distribution is total throughout the whole bed..

    Once again, it just depends on what your doing, Wilson would have been pulling out his lettuce as soon as they reached maturity, so root build up wouldn't be such a big issue.. I have a bed of cellery that I've been harvesting stalks from for over 12 months now without replanting. If it was continuous flow, I would be having problems by now due to the reasons mentioned above, but with the flood and drain you never have these problems..

    Frosty, I don't think copra is a very long lasting thing as it's only coconut firbe.. I have heard of some people experimenting with it, but I don't remember hearing any glowing reports.
     
  6. ~Tullymoor~

    ~Tullymoor~ Junior Member

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    Hi snaggs,
    Did you mean Travis W Hughey's set up is a "little untidy" or Joel's is?
    I can't look at the link Joel posted as my net speed is sooo slow, but I'm sure you must have meant Hughey's and not Joel's.....Joel's is lubberly :D
     
  7. Veggie Boy

    Veggie Boy Junior Member

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    I reckon Hughey's system looks fairly tidy actually - not as flash as Joel's, but the drums are kindof hidden for the most part.
     

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