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Prawn instead of fish?

Discussion in 'What Fish is that ?' started by Grimgrak, Nov 19, 2011.

  1. Grimgrak

    Grimgrak New Member

    Joined:
    Sep 23, 2011
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    71
    Would there be any problem using prawn instead of fish? I find prawns taste better than fish. What would you feed them? Do they eat veggies?
     
  2. Castaway

    Castaway Senior Member

    Joined:
    Jun 7, 2009
    Messages:
    2,472
    I can't see why not.
    You could feed them on high 38% protein crushed fish pellets or special shrimp meal.

    [YOUTUBE]DFIuBabdeiw[/YOUTUBE]

    Here's an interesting video clip from New Zealand where the owners have sited a RAS prawn farm right next to a geo-thermal power station and have used hot waste water from the power station to grow 12 ton per year of giant Malaysian Freshwater river prawns at a nice constant 28 degrees C. The prawns are eaten by patrons at their restaurant.
    Clever huh?
     
  3. watercat

    watercat New Member

    Joined:
    Nov 14, 2011
    Messages:
    32
    That is a great video. Now all i need to do is create a super volcano under my house.

    So my plan has always been to have fish, clams, freshwater lobster and prawns. I believe i have the fish part figured out. I have only read all the info i could get my hand on for clams and think i have the basics to start trying to breed some. I have been following a web site in Virginia i think it is that breeds the Malaysian giant fresh water prawn. Then of course are these red claw crayfish.

    I watched some you tube videos of crayfish being raised in fish tanks. they took plexiglass and fit and glued it together to make square tubes that just one crayfish could fit in. so they were stack like a small apartment building of fish in these cubicles. Not much bigger than a full size crayfish.

    I saw this and though that a IBC tank could be made like this but it would require the inside cubicles to be removable. What has come to mind is a tri pod lift or a four post lift over the or around the IBC tank. You could fashion the cray fish tank out of plexi glass or pvc pipe? Not sure about the clear part i though they liked dark holes to live in and pvc pipe or black sewer pipe is easier to work with and cheaper.

    I imagined these tubes built in such a way that every side of the tank would house different row of crayfish. and this tube structure would be from the bottom of the tank to just below the water line. So if it were say 3" tube you can imagine how many you could place on just one level all the way around the IBC tank. With many rows on top of each other. A simple hand cranks boat winch or a nice atv power winch for lifting the plastic pipe cage.

    Also it should be noted that attaching the plastic pipe together would be all done with glue and should be very strong as a whole.

    My reasoning for lifting the cages is to maximize the amount of cray fish in the tank but to allow you to farm them in deeper tanks taking up less floor space. My guess is to feed them you would lift the cages and place food in each tube. Sounds time consuming but it probably would not take as long as if you had more tanks and less density. easier to maintain one tank then ten. Since they can come out of the water unlike fish it seems viable for the hobbyist to be able to harvest enough often enough to make it worth while. Or maybe I'm off my rocker on this one. But it has been in my head for a couple years and i had no one to bounce it off of.

    I came up with this design trying to think of how i could manage the large fresh water clams in breeding to harvest. My first though was that a large amount of bi valves with a large amount of crayfish would make a good balance for water quality? totally a guess. But the design part was to have the fish that the clams attach them selfs to swimming in a IBC tank above expanded metal. this i got from reading about keeping male and female tilapia growing at the same rate as were you don't allow the female to mouth brood her eggs by having a floor that the eggs can pass through so she can not collect them and will continue to eat for that week she would have stored them tell they were fry. Cray fish under the expanded metal with a mouth brooder seems like a ideal situation to grow a fish cray fish with them and keep them separated.

    But for the clams my idea was as they breed and fall through the expanded metal the are safe from predators. at some point they can be vacuumed off the bottom of the with a water siphon or vacuum. then they can be placed in the clam grow out tank. I imagined it as several shelves with expanded type of material water could pass through. It would be raised just like the cray fish cage. but more like a bunch of cookie sheets with clams set on each by date or size for harvest. the best would be a different size hole in the material for every shelve. just suck the clams up from the breeding tank and squirt them in the grow out tank and the fall through the wholes to the correct shelf for size. Again since they can be removed from the water with out harm you can easily maintain them with a hands on approach and they do not need to bury themselves from what i have read to survive and grow.

    This again seem like a great way for a hobbyist to have a large volume of shell fish in a small area.

    The lift system is easy to build and can be wood or metal. remember your not picking up any of the water so its not going to be very heavy. Imagine 1000's of clams piled up on each shelf. from what i read the fish density would be much higher and healthier?
     
  4. Grimgrak

    Grimgrak New Member

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    Sep 23, 2011
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    Wonder if i could feed the shrimp ground up shrimp shells/body parts.
     
  5. Grimgrak

    Grimgrak New Member

    Joined:
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    Also what would you feed the clams?
     
  6. keith_r

    keith_r Member

    Joined:
    Jan 22, 2011
    Messages:
    157
    plankton, and microinvertabrates.. they're filter feeders..
    not many freshwater clams/mussels are edible, the ones that are aren't anywhere near as tasty as salt water bi-valves
     
  7. watercat

    watercat New Member

    Joined:
    Nov 14, 2011
    Messages:
    32
    I was told that we have large fresh water clam that was very tasty. If that's not true i don't want them.

    I wonder how hard the system would be to get the clam's food growing in the tanks. They must have a feed they eat I see them kept in small tanks but usually one or two.

    Some how i was thinking the fish density would be much higher to create the food for the clams.?
     

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