Backyard Aquaponics
A place to discuss aquaponics

Helftner feeds that makes the organic feed has a fire so now I cant get more feed from them. What do you guys think of using cow feed? I found a feed that is 20% protein and is "natural" with no animal products in it. If I grow out for 12 months vs the normal 7 to 9 months, do you think the fish would get big enough? Throw in an egg once in a while?

Tilapia can be grown with rice bran,Moringa and vegie waste ( in ponds)but take near 18 months to reach a decent size.
Those using good fish-oil protein based pellets grow-out in 5 months.
Most serious growers set amaximum grow-out period of 6 months,,,Tilapia show a substantial decrease in growth rate once they are over 6 months of age.

Feed cow poop?

janet I don't actually think he meant cow poop , but rather , food designed for cattle.
But YES cow poop ,, makes a nice algal bloom and the Tilapia will like that ,, but not a good thing for Aquaponics this algal bloom.

Janet, I guess if china raises their tilapia in algae blooms from human poop then cow poop might just work too. What if I make the bloom happen in a seperate tank then adjust the pH and feed the thick strands of algae to the fish?

My main gripe with most fish foods is the use of animal protein which comes from whos knows where.

Indonesia and the Phillipines utilise chicken manure extensively in raising Tilapia... believe the Thais do as well Chappo.... cages over/above the pond...

Here's an article for anyone's interest... http://www.fao.org/docrep/field/003/AC526E/AC526E03.htm

Thanks Rupe!

So, if tilapia can be grown in algae water, why exactly are we not doing it? Is it the pH swings or loss of oxygen over night?

I read somewhere that fish were being raised with algae which produced extra oxygen in the water. Does all algae produce oxygen? Is it just at night that algae consumes oxygen and shifts pH?

20% protein is 20% protein, as long as its digestable, and it probably is for tilapia

Article... and almost all the literature pertains to pond based aquaculture DD... not recirc tanks...

Had this discussion recently

Algael management in recirc systems just isn't practical due to the "small" volumes of water.. and pH, DO swings, temp etc... in recirc tanks, can be deadly in a matter of hours...

Even in ponds... can be deadly overnight... or a couple of hours into the morning depending on temps...

Rupe is spot on ,, chicken pens above the ponds ,, also pig pens with run-off water into ponds ..... any shi*t , including human ,, equals feed for an algal bloom ....., most SE Asian farmers have little education ,, but they know by what they have seen.
Actually you will see the Tilapia gather under the chicken coop waiting for some poop to eat ,, AHHHH ,, interesting.
YUK

Sorry Steve ,, animal protein is just superior ,, My much adored Moringa , high protein , but can only be used for 10-15% of feed before having a negative effect on growth:(
Sad but true.

In a sustainable sense I wonder how much better animal protein is. I mean, at some point some animal has to convert veggie or algae growth to protein. So if I am going to source ALL my system input on site. That means feeding fish plant based food which results in slower growth and an over all smaller fish. No problem, this is not commercial here. Now, if I want animal protein to speed fish growth I need to grow worms or other animals and feed them to the fish. This only shifts the conversion time of plants to protein to another species.

I guess the advantage is having the tilapia grow larger during the time that they grow the most and grow fastest. Is it really worth it for home growing? I can just grow more fish at the smaller size..

Now, for my needs, I need 2.4 pounds of fish food per day during full operation (as of now). BSF along with algae and veggie scrapps should be able to meet this goal; at wet weight anyway.

OK ,, you consider Animal protein to be a problem . You want to swap animal protein for vegetive protein.
Why are you growing fish?
Are you going to bury the fish under the lettuce?

At this stage , at this technological level ,, plants simply cannot suypply an equal protein .
Yes ,, you can slowly and inefficiently grow your fish ,, you have that right,,, but would that space no be better put to a usefull pourpose???

Animal protein from untraceable sources is a problem.

Yes, I was suggesting directly feeding cow poop to the tilapia. Glad some folks got that. I saw a show (Dirty Jobs) where the tilapia ate fish poop and crumbs left over from raising another table fish. Don't remember which one. Then they would harvest both fish.