permaculture

[georg parlow <g.parlow@gmx.at>]

> What kind of fish are you feeding? How did you come of with this  
> system

Last season I had common carp in it's wild form http://en.wikipedia.org/wiki/File:Cyprinus_carpio_1879.jpg 
 - not so fat as the variety usually bred in aquaculture http://de.wikipedia.org/w/index.php?title=Datei:Spiegelkarpfen.jpg&filetimestamp=20070513134009&; 
 - and very tasty! I suppose this is partly due to the fact, that in  
the aquaponic tank they are in a highly oxigenated environment,  
whereas usual pond culture is a lot less aerobic, which leads to the  
common 'pond smell' of the pond, and subsequently to the 'pond taste'  
of the fish.

How I came up with this system? Well, I was fascinated by chinampas  
and similar systems ever since my PDC in 1988 - and when I got the  
chance I read up on it on the www and then exactly one year ago I  
started my experiments.

> Much more sustainable than farmed fish using
> wild caught fish food.

I think it is sick to feed farmed fish food made from wild caught fish.

> > how are you making the pellets (pelletizing machines tend to be  
> > rather
> > large scale, finicky things).
>
> For small scale pellet production you could take Georg's  
> ingredients, mix
> them with some kind of binder
> to make a dough then run them through a hand crank meat grinder with  
> large
> screen.

Just like that, or almost. I do not use a binder, but the spelt flour  
is the binder.


> Have two people do it, one turns the crank, the other takes a knife
> and slices the "worms" off as they emerge and puts them on a tray to  
> dry in
> the sun before feeding.


Obvious thinking, this is how I started, but for me it works a bit  
different. When slicing the 'worms' of the meat mincer, the tend to  
stick together a lot more. It is best if I let them come out approx 12  
or 15 cm, then gently break the bunch off by letting it rest on my  
hand and sorta wiggle the bunch off. Also if they are so much longer  
they are very easy to separate onto the drying board (I kinda shake- 
drop them out of my loosly cupped hands). A day or two (depends on air  
humidity) later, the 'worms' can easily be crumbled up to make nice  
pellet size. The mix makes the diff - if too much grainflour, they get  
too hard, like dry noodles. And I gave up sundrying, as they go rancid  
very quick in sunlight - if kept in the well ventilated shade they  
last for weeks and weeks.

To find that out I was playing around with different mixes, for the  
thing is: if the mix is too gluey, the 'worms' stick together and it  
is a mess. If the dough is too dry, you do not end up with worms but  
crumbles. Here is my recipe:

2000 g ground sesame oil press cake
370 g whole meal flour
40 g rockdust
1300 to 1350 g water (might be a little different with other press  
cake - but the first few months I didn't measure and write down  
proportions, I was inventing the mix every time new, until I realized  
that developing a recipe has some advantage in this particular case -  
for as a cook i can't stand following a recipe)

Mix everything well, and do not be discouraged if the mix appears too  
dry - just grab a handful and squeez it into a ball - if it sticks  
together you are set. Otherwise you will regret it later on.

Upcoming season I plan to try Clarias gariepinus http://en.wikipedia.org/wiki/Clarias_gariepinus 
 - they are said to reach plate size in 3 to 5 months, and are really  
greedy gobblers. After week 20 I might be feeding 10 kg a day. So I am  
pondering the purchase of an electric meat mincer, or else I will  
spend most of my day producing fish food :)

Hope this was helpful.
Georg