AP for orphans-need some tech advice

[sa aqua]

ok so i'm moving house and while cleaning and purging all the stuff we don't need ie.2 kids =1000s of toys,we decide to go give it to a small orphanage that i drive past everyday.i'm a big guy and what i saw there brought me to tears for the first time in many years.this place receives no government assistance because most of the kids are white(so much for the rainbow nation)all assistance is by private donations.
enter the "400"group that im starting.i have a large group of friends that own their own businesses.each of us, 20 in all will donate R4OO(sorry don't know the conversion rate)every three months to a sustainable project to those who need it the most.our first project will be a AP system,that might make them more self sufficient and more importantantly educate them.this is where i hope you guys can help with some tech advice.this is what I've got so far.tank+-330l,growbed 1800x600x310.how many grow beds can i have?how many tilapia can i stock?thanks guys

[Murray]

Good idea sa aqua,
There is already a lot written in the forum about Tilapia and stocking densities, so if you use the search facility for both those you will find a lot about both subjects.
There are other members here from SA that will pop up and be able to offer specific advice I am sure.