Should I separate my Heinz 57 for better food

[Claude-Michel Prevost]

Hi there

I got these 50 tilapia:

http://www.flickr.com/photos/claude-michel/6662233013/in/photostream

The breeder told me: Mother is Nile, Blue:

http://www.flickr.com/photos/claude-michel/6643325563/in/photostream

http://www.fda.gov/Food/FoodSafety/Product-SpecificInformation/Seaf...

And Father is Mozambique, White, King:

http://www.flickr.com/photos/claude-michel/6566560267/in/photostream

http://www.mymomfriday.com/2009/11/steamed-king-fish-in-light-soy.html

Kinda the ND21 strain

http://www.aquaculture.co.il/technology/ND21.html

· Female O. nilotica  ND-2 Tilapia family line
· Male O. aurea  ND-1 Tilapia family line

Their next home is that barrelponics system still under construction:

 http://www.flickr.com/photos/claude-michel/6670723163/in/photostream

Now, I have a big difference is sizes and feeding frenzies:

2 to 4 extra large, mostly red and - I figure- male, able to engulf whole large food pellets 

6 to 8 larges, both breeds, also eating seriously

20 to 30 medium, both breeds, who can stand their own when comes feeding time.

The rest are runts, mostly Blue Nile, probably female, who wait for their turn or scavenge.

Good thing currents and bubbles carry pellets everywhere, and I give them plenty food (pellets, greens and algae wafers.)

But I still don't know

1) if the biggies are slowing down the runts by eating most of the food and

2) how much food is spent on each size group.

Now, should I keep the sizes separate? Is it worth it?

Thanks,

Claude-Michel 

[TCLynx]

If you are trying for commercial type growth, then you would be separating by size as well as possibly gender.

If this is just for growing some of your own food, well do you really want to harvest an entire tank full at once to eat?  Or would you rather just net out a few of the bigger ones when it is time for a fish dinner?  And do you even have the tanks to separate them out by size?  Or if you have one big tank you might make separate cages for the different sizes I guess.  And cage culture has the benefit of if you can keep the cage up off the bottom of the tank, the fish can't breed and so the females may still grow slower, they won't be spending weeks at a time holding eggs and not eating and therefore really not growing.

[Claude-Michel Prevost]

Hi TClynx,

I'm going for family food safety first, meaning growing veggies first and eating the occasional fish.

I have the large aquarium you see them in now, plus 2 smaller aquariums and bits and pieces of pumps and air stones etc.

I also have the front barrel from the barrelponics system where they will go as soon as I move it to Chuckleberry Farm's heated greenhouse.

If I read you well, I should use the present big aquarium they're in to separate them by size.

Cool.

Thanks.

I still don't know how to sex them.

I just assume the bigger ones - especially the pink/red ones -  are male and the smaller grey/blue ones are female. 

My eyesight sucks and just trying to catch of of these jumpy little bastards to check their assholes can be a real pain.

So I will sort them by size first, sex second. 

I have reserved 1 of the small aquariums for a nursery/hatchery.

I will keep you posted.

Cheers,

CM

[TCLynx]

I'd just say set up a cage to keep most of them for grow out so they can't breed out of control and you can just throw them in together then perhaps pick out some nice ones to be your breeders in the aquarium if you want to go to the trouble of breeding any of your own.

[Claude-Michel Prevost]

I've placed a - flimsy - divider to separate the big ones from the small ones  - the small ones actually manage to sleep by the side! When the dust settles down I will take pictures.

Thanks again.

Cheers,

CM