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New Modified double Indy 23 System

Discussion in 'Equipment' started by Raeto Z, Sep 19, 2017.

  1. Raeto Z

    Raeto Z New Member

    Joined:
    Aug 25, 2017
    Messages:
    4
    Country:
    Sri Lanka
    State:
    Western Province
    City:
    Colombo
    I am building a double indy 23 in Sri Lanka with an additional race track (total 5). I have 6 x 1000l tanks whereof 5 are used as fish grow thanks and one as airrated biofilter containing comercial biofilter media. I converted one media bed race track and use it as DWC. So I have in total 4 DWC race tracks and one Media based track. All are of the same size as the original indy 23 plans.

    I build a 4000 liter central concrete sump (coated with non toxic paint) underground. For filtration I intend to install a mechanical drum filter and a protein skimmer after the biofilter similar as in Koi Ponds. The drum filter shall improve the solids removal and also compensate for the eliminated Media bed race track.

    Additionally I want to install a UV unit between the sump and the Fish Tanks for the return water.

    I intend to grow Tilapia at the beginning and later on switch to Baramundi once I have more experience.

    I want to have a fish tank water volume turnover of 1 per hour.

    Question: Aquaponics design ratio - How big does the Bio-filter surface area has to be so that it will be sufficient not only to compensate for the eliminated media bed but also accommodate for the additional DWC track.

    I am aware that the Bio-filter must be calculated based on the feed input "load" and retention time of the water within the bio filter as if the water flows to fast the bacteria will not be able to complete the work as intended. (PhD Wilson Lennard's "Aquaponics System Design Parameters" white Paper is a good source of information but fully based on Media Beds only. Dr. James Rakozy has a scientific fish feed to plant grow bed area formula based on almost complete solid removal (which I will achieve via drum filter) but I have not been able to find it.

    I also air-rate the Fish Tanks, Bio Filter and DWC tracks so to oxigenize the water. A Cone and liquid Oxigen is to expensive here.

    Can anybody help me out here so to get the right design ratio's?

    I look forward to some creative feedback.

    Cheers
    Raeto
     
  2. Murray

    Murray Site Admin Staff Member

    Joined:
    Jun 4, 2009
    Messages:
    7,638
    Country:
    Australia
    State:
    Queensland
    City:
    Brisbane
    A UV filter will, over time, destroy the beneficial bacteria. You do not need to turn the FT water volume over once per hour. Every 90 minutes is OK, but that is up to you.
    Do you not have swirl filter or settlement tank as in the INDY 23 plans?
     
  3. Raeto Z

    Raeto Z New Member

    Joined:
    Aug 25, 2017
    Messages:
    4
    Country:
    Sri Lanka
    State:
    Western Province
    City:
    Colombo
    Hi All

    It has been some time now and I made great progress with my AP setup and the farm in general. I'm about 85% complete and hope to be ready in about 2 months to startup the system for the first time. I made some modification of the original plan such as:

    1. Installed and Increased underground sump to 5000 liters. Did not use the IBC's intended to be install under the race tracks.
    2. Increased the number of IBC Fish Tanks to total 12 units.
    3. Added another race track so in total 5 lines.
    4. Use only one full race track filled with Media (3/4 size stones) and use the second original intended media bed as DWC. The mechanical Drum Filter and installed Bio filter together with the media bed will be sufficient to handle the nitrification process i.e. feed quantity. The integrated UV filter can be switched on or off as Murray had some concerns in this regard.
    5. Going for Barramundi at the final stage Instead of Tilapia as the fingerlings and commercial feed is available here now.
    6. Facing some upper greenhouse temperatures but try to compensate with a water cooling system as controlling the root temperature is more effectife than the leave temp.
    7. Looking for some 40% white shade mesh to be installed in the greenhouse above the race tracks provided the control of the water temperature is still not enough . The fish area is covered with 60% black shade mesh. Does anybody know where to get white screen shade mesh in Asia?
    8. Installed 4 x 5k/L Rainwater collection tanks with a swimming pool water filter, UV Filter and pump for the rainwater circulation only. This way I can ensure sufficient clean water being available as and when required. Installed a first flush system on the gutters to avoid or minimize the initial wash off to enter the tanks.


    Have all nicely documented with pictures and all but am simply to busy to post them. Will do once the system is completed for start up.

    Cheers
    Raeto
     
  4. Agnes Harmers

    Agnes Harmers New Member

    Joined:
    May 21, 2018
    Messages:
    11
    Country:
    The Netherlands
    State:
    Groningen
    City:
    Groningen
    Hi Great! Did you start up?
     

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