Results 1 to 5 of 5

Thread: Aquaponic Lawn?

  1. #1
    Members
    Join Date
    Mar 2014
    Location
    San Francisco, CA
    Posts
    18

    Aquaponic Lawn?

    I just read another article about the on-going/deepening drought here in the western US. As with a lot of these articles, they talk a lot about people tearing out their lawns because of how much water they consume.

    http://www.nytimes.com/2014/03/13/ga...new-green.html

    From what I've read it seems that lawns in general... at least the way folks typically do them here in the US, are super resource intensive/wasting. Another article that I read a while back said that the average US lawn gets way more fertilizer, pesticide, and herbicide, than even the worst of the industrial agricultural fields... which was pretty surprising.

    Got me thinking that there must be a better way!?

    At least on the water front, I would think that a recirculating aquaponic system would have a huge benefit.

    I'm not sure what the best approach might be though. Anyone tried/heard of an aquaponic lawn?

    I'd kind of like to try one in my backyard.

    Turns out that my back yard (like most unbuilt land here in the city) is pretty highly contaminated with lead. Luckily we are below the "hazardous waste" cut-off, but it is not a good idea for kids, or really anyone, to play out there, and you don't want to grow green vegetables either. The traditional solutions are either to pave it with concrete and call it a patio or dig out the top 18" inches and ship it off to be someone else's problem. I'm not very psyched about either solution.

    I was thinking of sculpting the surface a bit, and then laying a HDPE pond liner over it. Then put down a layer of sand and gravel, then some porous pavers for drainage, and then try and build a new soil bed on top of that.

    The question though is if I might be better off going soilless and making the whole thing into one big aquaponic grow bed? Clearly I'd need a lot of fish to feed that much grow bead (approximately 30'x30'). But it would be super cool if I could figure something out that my kids could play on/in.

    Just throwing this wacky idea out there. Anyone have any suggestions?

    B

  2. #2
    Members
    Join Date
    Sep 2013
    Location
    South Australia
    Posts
    21

    Re: Aquaponic Lawn?

    Hey Billy

    This is an interesting idea. I've not read much on this, nor have I come across much info on it.

    with a quick google search I found a youtube video of someone growing wheatgrass aquaponicly, looking at it, it does seem like you could get the density you need to be able to call it a lawn.

    Also I have seen articles on growbeds that use hydroton and soil, this might be the best way to go about growing grass.

    However things you might what to consider or look into, is if you can grow a type of grass you want, and then if you did it, would it be stable enough to walk/play on, could walking on it cause compaction, if it does cause compaction, is this ok, will compaction reduce or block the flow in or out of the "grow bed" and if you are walking on this, will the grass survive.

    please note that I'm not an expert, so I'm only applying the logic I have from what i do know.
    I still find each day too short for all the thoughts I want to think, all the walks I want to take, all the books I want to read, and all the friends I want to see. -John Burroughs

  3. #3
    Members
    Join Date
    Mar 2014
    Location
    San Francisco, CA
    Posts
    18

    Re: Aquaponic Lawn?

    Thanks Druid.

    I've done a bit more research and thinking on this subject, and I think that a relatively small gravel of red lava or crushed brick would likely provide a good stable surface for walking while also providing a decently porous medium. My local rock crusher has a 5/16" (8mm) size that I think is "packing" and so would likely do well. Various folks on hydroponic forums say that red lava gravel and also crushed brick are pretty good mediums once you wash out the dust. Clearly I will have to run some experiments.

    The biggest question that I am currently stuck on is this...

    In virtually every aquaponic system design I have seen so far, the growbed is elevated above the fish tank so that the ebb&flow system or the NFT can drain onto the tank. But I don't really want to install a big fish tank underneath my lawn! I'm kind of hoping to have it above grade in a shady corner, or in my garage or something.

    So, I've been trying to figure out how to re-organize things so that the fish tank is above the lawn surface. It doesn't strike me as an impossible idea, it just that I've just never seen it done before. Anyone seen/worked with this sort of upside down type arrangement?

    Also, the lawn is a pretty small lawn at approximately 30'x30', but that is kind of a tremendous growbed! I would like to ebb&flow it, but to do the whole thing at once would require a super massive fish tank! Based on Oliver's 2:1 ratio from the Aquaponics 101 series (still super impressed with that terrific piece of work, thank you Oliver) that puts me at a 3400 gallon tank! Which is bigger than I was hoping for. I was kind of thinking of using 2 or 3 IBCs rather than 14!

    I've thought about reducing the grow bed depth to 6"... as the grasses that I have been digging up lately all appear to have pretty shallow root systems in regular soil. This also cuts down on media costs/hauling.

    But the real question is whether I might be able to divide up the grow bed into smaller areas (maybe some 6" for grass and others 12" for vegetables) then I might be able to rig things up so that while one growbed is filling up, another grow bed is draining down so that I don't stress my fish with water fluctuations, but I still have a lot of the water in the system out in the field most of the time.

    Bill

  4. #4
    Members topz's Avatar
    Join Date
    Sep 2013
    Location
    Omaha, Nebraska
    Posts
    138

    Re: Aquaponic Lawn?

    Put a sump at a low point, pump from the sump to your tank. Use a constant height drain with a solids lifting pipe to flow water back from the tank to the grow beds As for the grow beds split them as you see fit just drain them to the sump and get a decent pump to handle the flow.

    Just one way this could be done.

  5. #5
    Members
    Join Date
    Sep 2013
    Location
    South Australia
    Posts
    21

    Re: Aquaponic Lawn?

    Hey Billy

    You're welcome, not sure how much help I can be on this subject.

    I have thought about "upside down systems", as far as I know, the only way you can do it this way, would be with the use of a sump tank, however this still leaves you with the matter of having a tank lower than the grow bed (at least not with fish in it though).

    I'm not sure if that is a possibility for you, but I think that would be your easiest bet, while maintaining an ebb and flow system.

    I really don't know much about sumps or setups that involve them, so I can't really give you much more advice on them sorry, just know that they can be used to carry water from a grow bed to a higher fish tank.

    On the topic of dividing up the grow beds, I would suggest still using one grow bed, as its said that the bigger the setup the more stable it will be, and then just sectioning the grow bed with some kind of guard with the same idea as your gravel guard (allowing water through but not gravel).

    To help you calculate your volume you can use this method: Length x Width X Height divided by 231 for gallons or 1,000 for liters

    So for your proposed grow bed: calculated in inches (roughly)
    At 6 inches height: 360 x 360 x 6 / 231 = 3366.23377 gallons (lets say 3367)
    At 8 inches height: 360 x 360 x 8 / 231 = 4488.31169 gallons (lets say 4489)
    At 12 inches height: 360 x 360 x 12 / 231 = 6732.46753 gallons (lets say 6733)

    I'm not sure about other media, but if memory serves hydroton displaces about 50% of the water in the grow tank, so only half the volume in that grow bed will actually be water.

    This makes the water requirements for 6 inches is 1683.5 gallons, 8 inches 2244.5 gallons and 12 inches 3366.5 gallons.

    If you could find media that displaces more water you might be able to bring you water needs down to something you might be able to use an IBC tote for.

    I think that about answers all the questions I have answers for, that said, do please research the info I have given you as I am no professional... yet

    Hope this was helpful.
    I still find each day too short for all the thoughts I want to think, all the walks I want to take, all the books I want to read, and all the friends I want to see. -John Burroughs

Similar Threads

  1. Hello from Fair Lawn, NJ
    By sdanchenko in forum The Welcome Lounge
    Replies: 34
    Last Post: 04-10-2014, 02:45 AM
  2. Want to visit an Aquaponic farm in NJ...
    By VictoryGarden in forum Speak Up..!
    Replies: 11
    Last Post: 09-25-2013, 12:42 AM
  3. Aquaponic Armageddon!
    By bsfman in forum Aquaponics Knowhow
    Replies: 30
    Last Post: 04-21-2012, 04:37 AM
  4. Looking for Aquaponic Stats.
    By cenapatuct in forum Want To Know HOW TO..?
    Replies: 6
    Last Post: 03-15-2011, 07:52 AM
  5. Penthouse Aquaponic System
    By Lagartijo in forum Back Yard Systems
    Replies: 8
    Last Post: 03-18-2010, 01:07 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •