Backyard Aquaponics
A place to discuss aquaponics

Being 8 days until marron season I thought I might get a licence and some gear and see how many I can get (I've never tried before, never eaten marron and only actually seen one once).

I want to keep some to start with aquaponics but I'm not sure what containers to use. The local hardware has a couple of blue drums for $28ea or some shorter/wider white drums for the same price. Would these be deep enough cut horizontally or vertically for marron to be comfortable?

What other cheap containers would be suitable for marron? I've seen the rectangular storage containers but all the ones i've seen look a bit flimsy to be drilling holes into.

Cheers

I read that marron can live in as little as 15cm of water but if the water temperature goes above 26C deaths may occur. I only just got some so cant speak from experience

I am just going to use an old esky, but im cheating, im buying mine for a dollar each from a farm. I only getting 8 and they are between 5cm and 10cm.

..and i also heard the same as brett..

Jonezy, simmo 77 had marron in smaller type containers it may be worth looking up his thread

http://www.backyardaquaponics.com/forum ... highlight=

We have marron in an old shutz tank cut in half, it is about 50 cm deep but we only fill the water to about 30 cm. They are amazing creatures and can climb out if the water is too near the top of the tank! We also have a mesh covering over it, again to ensure they don't get out and to keep predators away. The temperature is critical... we have a cheap, small water fountain pump we run in the tank on hot days to keep the water circulating, which helps. Have fun!
dandm

I've been thinking about this lately.
My first idea was to have a stack of shallow tanks one on top of the other to get as many crayfish into as smaller space as possible.

Then I saw the pictures of commercial crustacean operations where they use multiple layers of shade cloth or plastic bins that are then lowered into tanks (does anyone have the link). This really increase the surface area and hence the stocking capacity of a tank.

I'm still wondering how you would feed a territorial species like maron or yabbies so that they all got food. With fish you just throw the food in and it gets eaten. With yabbies (and I presume maron but maybe not as much with with red claw). Ie in a stack of plastic trays how do you get food to all the trays that are not on the top and spread evenly through out the tray so that one animal can't hoard it all.

With great care if you don't want to lose a finger

Don't know but I suppose you could have an arrangement where you pull them out of the water chuck some food in each one then drop them back down. The don't seem to get get stressed like fish being out of the water a few minutes.

good question and so goes the age old question of high density living.
how about a food shute to each level?
Sounds a bit like battery chickens, don't know if I want to go there.

It's not like battery chickens its like bacteria :tongue1:

How many crayfish/prawns etc is mostly a function of surface area just like our bacteria. There is also a sight component though.

So if you have an IBC with just water then you might only be able to have about 9 large yabbies (each roughly requires 30cm x 30cm). If you add hidey holes and reduce the lines of sight you might be able to bump that to 12. Cloud the water with colloidal clay (clay that does not settle) and you could increase the stocking a little bit more.

The idea of mulitple layers is just another way of increasing the available surface area. Another bonus of the stackable trays is that you could grade the crayfish of different sizes into different trays.

I have an idea for keeping my yabbies (in 2 years when I have time to build it)!
If anybody has seen architects drawers, big enough to fit an A0 drawing it will help this idea.
Build a frame 0.8mx1.6m, 1m high
add drawers to this frame, 200mm deep.
place a vertical standpipe overflow drain, so excess water falls to the next draw (standpipes must not be directly over each other)
Fill with water at the top.
water will overflow into the second drawer
water will overflow into the third drawer and so on.
pull out drawer 2 to do some work... drawer 1 now drains into drawer 3 not drawer 2 right?
place dividers in each drawer with enough room to make a yabbie happy, 200mm*200mm maybe?
Place a guard of some sort (stainless mesh) over the top of each divided area.

now you should be able to fit 4*8 = 32 yabbies per drawer.
so 4 drawers = 128 yabbies in luxury comfort.
Then every day open a drawer and drop in bit of carrot each (grown via AP of course :-) )

Wouldn't you only get 31 per drawer because of the standpipes?

ummm perhaps we could squeeze the standpipes in and make a couple a might smaller, 200mm square for standpipes is a tad over-engineered - not that there's anything wrong with that :-) would certainly make cleaning easier :-)
ok so 31*4 = 124... not a big difference.
Also, we could perhaps make the drawers bigger?
Or have 5 or 6 rather than 4?

On an aside:
Yabbies to me, if I had 120 odd, would all get harvested at once, and most would be precessed into different food stuffs. I don't see the need for gradual year long harvesting like I do with fish.
So 120 would be plenty plenty, I don't think I'd have more drawers.

guys in Thomastown have a patent pending system. It revolves around a series of cigar shaped capsules connected to a verticle column. Each capsule has holes in it so food can enter from the water as it is circulated. The yabbie never leaves this capsule until it is harvested, even eats its own moults. Growth is quicker than normal, (they are well on the way to a yabbie specific nutrient profile.)
They are also harvested in pristine condition and therefor attract premium pricing.
You can't get anywhere near RAS stocking densities so your price needs to be higher if ur doing it commercially. There is no worries about selling ur product bc yabbies are undersupplied to the trade.
Aquaponically, scrunch up some shadecloth, with a lambtail ring in one end and dump lotsa these in ur water. It creates lots of hidey spots and increases ur stocking density. You might have 3-4 live on one piece of shadecloth, instead of one in that spot on the base of the tank.

Was not really picking KP, jut took me a while to get an image of what you meant. Still heck of a lot of yabbies

Only thing I worry about is the ? ethical/moral side of keeping things in seperate cages, does not make me feel good.

Kp's idea wouldn't really be keeping them in separate cages though. Each would have its own little bit of space and hidey hole.

No less humane than a block of 1bdrm apartments.

Ohh never mind