First System: Recycled and Aesthetic

[Guru Das C Bock]

I have been running this new system for 3 months and all is going well.  This system is made of recycled materials and hosts 11 koi fish and 1 plecostomus.  The fish tank holds 180 gallons and the medium for the grow bed is locally sourced creek-bed gravel.

This is my first system ever and it took me a lot of research and imagination to figure out the right design.  The method I chose is a continuous flow through the gravel with a single standpipe.  The water exits the bed and splashes back into the fish tank below for aeration.  No problems so far.  We have gathered a surplus of melons okra beans corn tomatoes and tobacco.

As we live in the Sonoran Desert, temperatures may be extreme. That is why i chose a continuous flow system with a simple standpipe overflow. Electricity is consumed by a single pump which fills the gravel bed and aerates the fish tank at the same time. The fish tank is submerged in the ground for thermal mass and to slow any extreme temperature changes.  It is not uncommon for the temperatures here to vary 40 degrees F from day to night.  Also the fish tank is covered by the gravel bed and lumber box to prevent evaporative losses in the 100+ degree F summer temp.  Everything transplanted so far has survived and thrived.  Ammonia Nitrite and Nitrate levels are always close to zero.  The PH is just above 7.  And average water temp is 70 deg. F.  I have placed an old wrench found in the desert directly in the gravel bed as a source of iron. 

Please feel free to reply with any comments suggestions.

http://1144s7thave.tumblr.com/post/33142602183/the-evolution-of-our...

[Guru Das C Bock]

here is a pic of it, same as the one in my thumbnail.

[Jon Parr]

It is a thing of beauty. Congrats. I would suggest that you add a larger diameter pipe (with a castle-cut at the bottom) over (around) your standpipe. This will allow the top-flow standpipe to draw water from the bottom of the grow bed, improving circulation of water, DO, and nutrients. Also, a piece of iron in the system does indeed add iron, but not usually iron that is available to the plants. If the iron remains rusty, then you are only adding iron oxide, or ferric iron ions, which are NOT plant usable and are toxic to fish to some extent, physically blocking gill function like us trying to breath in a sandstorm. If the iron is placed at the bottom of the gunkiest, most anaerobic (sewer-smelling) corner of your media (which shouldn't be hard to find in a constant flow bed), then it will turn black, and may produce some organically chelated iron, or ferrous ions that are plant usable. Also, keeping your pH just above 6.0 will let the ferrous iron last longer, and most all nutrients will be more available and your plants will thank you. Very nice system, well done.

[Guru Das C Bock]

Thanks for the pointers Jon.