Making your own feed

I agree. Pulp mostly contains cellulose and should be fed to animals that need/ want a high cellulose diet. Worms and/ or rabbits would be my first choice. Feeding veggie pulp to fish only adds roughage. Cellulose is best broken down by microbes so the compost bin would be my third choice to keep the nute loop closed.

Anybody know anything about the nutritional value of hornwort?  I am growing it floating in all my ornamental tanks and feeding it to my tilapia.  I do this because I have the plant and it grows quickly, however, I have not seen any kind of nutritional information for hornwort (I can find lots on what it needs to grow, but not on its value as a food source).

@ Ellen: Sorry, I've been out of Labs for years so no answer but interesting idea. I would guess the nutritional yield would be similar to lichen and mosses.

Well if the fish eat it then worst come to worse it may be good roughage. Does it grow fast enough to actually feed your fish or how much do you compliment?

@Carey: No, it's currently about 25% of their diet by volume.  The rest is pellets and whatever they can catch on their own.

I need some advise, I mistakenly bought extra small bsfl from phoenix worm hoping to make a colony to feed my fish. I bought about 300 and yes they do eat but it seems it will take longer than I want for them to get bigger and start laying eggs. Now im thinking I should buy some large ones to kickstart the process, how many do you think I should buy?

@ David S: I use to make my own feed when i had more than five hundred tail of fish. I also made feed when I was working with an NGO that had a decent sized pond. Now I have several types of Ap involvement including a small home system and a small Ap store. I also actively consult with different agricultural entities in hopes of integrating other aspects of farming to reduce down-line byproduct waste for more ecologically appropriate management. I manage three ponds totaling almost three acres for a feed manufacture and next year hope to cooperate with a few fish farmers to introduce Ap as a form of biomitigation while increasing profits.

As for BSFs: I have no clue because I don't have enough information. How long have you had them? How much waste/ food input is available daily? How much do they eat%? How big is your grow container? What is the surface area? How many fish do you have to feed? How much money do you have? How much do they cost? If you have a kit; what does the manufacture suggest?

Two things to remember. One is that there cannot be too many, only too few. If their food input supply is fairly constant, they will increase/ decrease automatically to a balance. Two; If conditions are appropriate, it still takes a required amount of time to mature. I suggest maybe run it a few cycles and see if the total output is what you need. If you are putting too much food for them to soon and rotting occurs, lessen the amount of your input. You may run a new system of larger variety to compare output efficiency.

I don't raise BSF deliberately like I do with red-worms and crickets. They come naturally in the compost pile which is where I put my molting or recuperating hens.

David, just be patient, it won't take as long as you think.  Save your $.  This guy has great BSFL advice.  See if you can glean anything from him http://diyaquaponics.com/forum/viewtopic.php?f=83&t=1331

http://www.cals.ncsu.edu/waste_mgt/smit ... les/A2.pdf

read this report completely and you can see the advantage of BSF larvae.  Take note of amounts used to obtain best results in catfish fingerlings

Don't forget that sprouts are a good source of nutrition. Grow some sprouts of grass/ fodder with your left over seeds. Chop em up and feed them to your fish.

Every time we buy bean sprouts we never seem to eat the whole bag. I feed them to my Blue Tilapia and they love it!

Great example David. You might try growing some by yourself. It's easy. I make sprouts every day for all my animals, more in the winter and less in the summer.

Thanks Carey. I grow lots of wheat grass and other micro greens for my family to eat and give the excess to the fish. I am not quite as good at the bean sprouts but I will give it a try. I figure the more self sustained input I can provide the less I will have to rely on those commercial pellets. I would love to figure out a way to have an organic feed I can make, that can supply most if not all of the necessary inputs for my fish to grow quickly and supply my plants with the elements they need as well. Thanks for sharing all of your knowledge! It is fascinating reading all of the things you have done and are doing. Great articles!

I am looking for a good system to grow sprouts.. any suggestions?

For most of my sprouts I use a standard black seedling grow tray that I get from my local hydroponics store for a dollar each: http://www.4hydroponics.com/growroom/items.asp?ItemNo=blackPropTray  The humidity dome is about $5 ea. http://www.4hydroponics.com/growroom/items.asp?ItemNo=tallDome They come in black and white and I use a simple 4' shop light from Home Depot $10. I used to use sure to grow pads as a media but through trial and error I have found using no media works just as well. My wife does bean sprouts in Mason jars but it seems like a lot of work as she washes or rinses the sprouts out a few times a day as they are germinating. Any time she forgets to do this or we leave town for a day or two we lose the sprouts. Otherwise it's pretty basic. The best trial would be to go get some wheat grass seeds from the supermarket/organic grocery store's bulk food section, lay them across the bottom of a tray, mist with water and cover with humidity dome. Wait about 4 to 7 days and you will have 4" to 6" tall wheat grass. cut with scissors and juice in juicer...delicious and nutritious! 

Important thing to know for growing sprouts (where you eat the seed and root and all) is you want seeds that are clean of any seed born pathogens so you either need to sterilize the outside of the seeds before sprouting or get seeds that are For sprouting.  You need to do the rinsing regularly (or set up some means to automatically do it) with clean water since raw sprouts grow quite nicely right along with some of the bacteria that can be less than comfortable to consume/eliminate.

The Shoots like David describes where you are cutting the shoot above the seed is far safer and easier but definitely different than sprouts.

That's true! My bad, we do rinse the wheat berries and seeds we buy in a very light vinegar/water solution and then rinse well before during and after sprouting. You should really do some research on the topic before feeding your loved ones any "experiments." Sorry to leave out a very important step

This is what I do to grow sprouts. Get a trusted source so you know it's not contaminated internally.

I fist wash my seeds in a container that holds twice the amount of seeds in a weak hydrogen peroxide. Then I pour this water out and replace with fresh water. The seeds then are poured into a clean pillow case, then placed in the soaking container where water is circulated over the seeds for few hours (4 – 8) depending on type of seed. Once the seeds begin to crack they are poured onto trays that are on scales to determine amount. I use commercial restaurant glass trays that are about 1.5’ times three feet, which holds about 2.5 pounds of seed. These trays are placed in the bottom slot of portable racks, which are placed in the shade side of the greenhouse. Each day the trays are moved one slot up and at the end of the cycle (top trays) we have ten pounds of edible (feed) product.

Cropking offers a similar set-up.

Common causes for sprouting failure:

• Dirty equipment
• Insufficient air flow/ humidity too high
• Insufficient rinsing
• Contaminated source of water or seeds (internally)
• Roots/ shoots are allowed to dry out
• Seeds are left in standing water (not enough oxygen)
• Air or water temperature is high or too low
• Poor rate of germination of seed

hello, my name is Marty Lininger.  i live in central FL.  i am interested in producing my own pelletized Tilapia feed using duckweed as a major component.  i also hope to process my own fish.  that would give me fish carcass to add to the feed.

  i am interested to know if anyone is pursuing similar ideas.

Have you done much research into pellet mills yet Marty?  Here in Central FL if you have a huge source of bio waste or food waste you might be able to use bsf larva and  or worms as a animal protein source to make an alternative to fish meal after rendering but the processing is probably a bit more than the average backyard enthusiast is up for.  (note to self, the cook won't let me render worms in the kitchen.)

duckweed vs azolla

a friend, Maynhia, turned me on to azolla as a better choice to duckweed. A little research showed me: azolla has higher protein and other minerals compared to duckweed.

My first try of azolla: My fish prefered the azolla to duckweed. I had to purchase it again. Now I have azolla growing good.

My source. http://jandjaquafarms.com/

Now I am growing chaya and moringa.. suggested by Gil Romero Yucatan.

easiest plants to grow. 

passing it forward,

Dave

i have done some research on pellet mills.  i am a little confused about the difference of pelletizing and extrusion though.  some descriptions make them sound like the same process, and some make them sound different.  my concern is that extrusion is touted as the way to make feed float, and pelletizing makes it sink.

i have not spent much time considering BSF or worms because they seem to be labor intensive to remove from their grow medium.  always looking for more info though.

as far as azolla goes, i would be interested to know what mineral advantage it has over duckweed.

what i like about DW is that it grows so fast, and has high protein (if you harvest it young - maybe that is why some believe azolla has higher protein, they compared to "old" duckweed?)  also, Omega-3   i want to have high Omega-3 Tilapia and i believe it can be done with DW, many studies show DW given to chickens produce Omega-3 eggs, and now you can buy those in the local grocery store, for a premium of course, just like my hoped for Omega-3 Tilapia

Has anyone attempted to breakdown the overall amino acid requirements for tilapia (or a specific type) and compared this with common feed sources? I assume the degree of error in the amino acid composition is going to be high however. I am going to assume carb and fat content sourcing is easy but you would require a minimum of 2 sources for protein and at least 2 more for required minerals to formulate a complete diet. What works and what is economical for producing a feed is going to very greatly based on location, or really a specific source, not the ingredient itself.

FYI there was a derailed thread with some links posted here.

This has a couple interesting links embedded.

http://documents.ponics.org/sections/aquaculture/aquaculture-world-...

This one is an interesting case study regarding small scale feed formulation in developing countries.

http://www.worldfishcenter.org/resource_centre/WF_2462.pdf

Chris & Marty &

thanks for the great info.

I am hoping to get off the grid and limit my driving to town, Making my own fish food is of interest for me. I like the azolla, but I also want Omegas. I will do further research. Thanks

I would love to eventually see a community sourced guideline document that can outline supplementing feed come about from this group. I think developing a cut and dry DIY feed recipe that can be used as a complete source is not practical to apply for universal purposes (mostly due to cost, labor, and complexity). Using control groups it would be interesting to see how far you can supplement commercial feed with various combinations of ingredients without impacting an overall aquaponics system.

Marty, whether or not one uses BSF should not hinge on removing them from their grow medium.  They do self-harvest (crawl out into a collection bin).  I don't have lots of worm experience but my impression is that removing them from their grow medium is not as simple as for BSF.  Glenn Martinez also points out that pound for pound his worms fetch a higher price for him than his fish.

LOL, yes separating worms from castings is labor intensive.

BSF larva though do self harvest and if you are in a warm enough climate they are great, cold climates require a big greenhouse to keep them going year round though but I believe Growing Power has done it.

Duckweed can supplement for up to 50% of commercial feed for tilapia without a loss of weight gain, that is the only easy guideline I've heard so far.

Worms and BSF larva are also great supplements but they are too high in fat to be a complete feed.

Algae and green water culture can be a great way to feed tilapia but that is not really appropriate to aquaponics but is more for extensive pond culture or solar algae pond production.

Now Carey has some great ideas for feed so watch his posts closely and pick up what you can.

As to feed mills or extrusion.  A pellet mill really just compresses bio-mass or whatever you put in it and I don't expect that it is easy to make floating feed that way.  Extruded feed is probably a bit more like making a dough and extruding it in an appropriate environment that it will contain enough air or light material to make it float.  That is probably a gross oversimplification of the concepts so hopefully some one with more technical experience in feed making can chime in and share more on the subject.  I have used a meat grinder with it's blade removed to extrude something like fat spaghetti that could be cut into pellet size pieces and dried or baked but that was an incredibly labor intensive way to make fish feed and I wouldn't recommend it for more than just testing a recipe.  (and using the kitchen to make fish feed is at your own risk because the cook may ban you from the house if you get caught. )

Why not grow both duckweed and azolla. In the wild they grow together. This would give your fish a more diverse diet. Azolla makes a great green fertilizer because it is nitrogen fixing. I would stay away from growing Salvinia.

Wow! So much interest recently. I apologize I haven't and can't respond at this time, however, I promise I'll do my best next weekend. I just came back from down south for a consultation and am leaving in a few hours for another consult so catch ya guys next week.

Cheers

PS There are basically two schools of AP: Clear-water vs. Greenwater culture. Both have their own requirement and methods of feeding. In clear-water culture, it is best if each function is separated; grow algae in the algae tubes and grow duckweed in the duckweed trays (they have different needs).

Just remember, unless you overstock your tanks, you will have to share "energy/ nutrients" with your veggies so maybe choose which is more important, raising feed or raising crops for market?

IMO the purpose of AP is not so much to raise an organic crop for market but to raise fish and have a natural, ecological way to filter "pollutants" with edible crops as a nice byproduct. Soil based crop raising is still by far the easier and better way to grow veggies vs. AP crop production.

What I would like to see is a volunteer group that is willing to compile a list of feed inputs and their approximate nutrition values. I'll start a page in this group for y'all to help yourselves so please stay tuned next weekend.

I want to estimate the size of duckweed bed that a specified fish population can support.  Any feedback I can get on my assumptions validity would be greatly appreciated!  Perhaps there is a logic error in my steps to calculate the size, please let me know!

My final calculation below seems to be way too much.  I do not know where I am erring.

Assumptions:

fish incorporate 30% of protein in feed, the other 70% is converted to ammonia  (1)

can get 95 gram of ammonia from 1kg of protein fed    (1)

1 gram of ammonia will feed 1 SM of duckweed  (2)          

duckweed can double in 4 days or less

constant population mass 1000kg of tilapia,       FCR of 1.5

consumes 1500kg of 30% protein feed in 1 year, consumes 450kg protein

 450kg protein x 95g ammonia/KG protein  = 42,750 g ammonia

which can support 42,750 SM growth of duckweed

harvesting half the crop every 4 days = 365/4 = 90 harvests

42,750 SM / 90 = 475 SM growing area per 1000kg tilapia fish

Other:

1SM of optimal density duckweed weighs  0.1 – 1.2 kg (0.65 avg) wet and is 93% water (3)

1 SM of optimal density avg 0.65 kg wet duckweed weighs 45 grams dry

1 SM naturally occurring duckweed in Orlando, FL dried weighs 100g  (4)

ref;

(1)    http://www.fao.org/docrep/X5744E/x5744e0e.html

(2)    Kobus Jooste post

(3)    Various sources

(4)     Own observation -but was it optimal density?

What is the protein content of duckweed again? Assuming perfect conversion and assuming the constants are accurate, the nitrogen seems to be all accounted here, but showing only 10% protein content of the fish. So it is likely you are correct that your number is a little big, because even going backwards and coming to a smaller SM value, it is still too big, but not totally off.


I think the degree of error here is the density of what a square meter of duckweed is, and the degree of error is very big, and will vary depending on localized conditions. In conclusion, likely not something you can solve with pure math, you need to grow it, dry it, and measure it all out :)

consumption is 1500kg feed/year = 4.11kg/day
1m2 duckweed = 45g
daily requirements 4.11kg/day / 0.045kg/m2 = 91.33 m2/day
duckweed per harvest every 4 days = 365.32 m2
Required space for doubling effect 730.64 m2

ammonia production per day (1500kg x 30% x 95g ammonia/kg = 42.75kg ammonia) / 365day = 117g/day
daily duckweed ammonia requirements = 91.33g/day
remaining ammonia 25.67g/day
ammonia consumed 78%


remaining ammonia per year back to fish protein 9.37kg ammonia /95g ammonia/kg protein = 98.63kg protein
protein content of 1000kg of tilapia / 98.63kg protein = 10.1%

Plus they cant live on 100% duckweed, so would have to half that value of course. The point is the number is still pretty big, and you can only find what it is with experimentation. Time of year and how fast it doubles can also change the area required in a big way.

Sorry

As soon as my mind knows there is math.. I shut down.

I have had to deal with that my whole life. Anyway, I have tried the yoke out of a bioiled egg. I have one of my males who will fight all for it. So I have started breaking it up into small pieces.. My fish seem to like it. I just started to add it into my new fry tank.. let you know what happens. Or comment back to me .. good or bad.

thanks Chris.

this is for growing duckweed, not feeding it, if that is what you are thinking. 

while i intend to use other feed sources, i wonder, if grow speed is not a factor, why you could not use duckweed alone if it was seeded with the minerals the fish needs?

I was using it as 100% feed to try and account for the nitrogen in a full circle to see if the quantities and constants made sense. I think the degree of error is just too much to come up with a semi accurate number.

You likely cant feed the fish 100% duckweed because its amino acid composition is likely not 100% ideal for fish protein requirements so multiple(or at least 2) protein sources are needed and of course all of the micro nutrients as you pointed out. It is probably lacking in energy(carbs/fat) somewhat too.

good points Chris.  at the suggestion of Paul Trudeau i have been spending time on BSF research and am glad to do it.  i had grown weary of bugs after researching crickets, grasshoppers and redworms and thought BSF another rabbit hole.  here i now sit with my initial 330 SF BSF building plans... 

regarding BSF.  does anyone have information regarding production capacity over time?  all i could find on WWW was 17.5 #/SF-year, but that article was not too clear.

I like azolla, chaya, moringa, and egg yoke mixed together with chicken parts not eaten. They are all easy to grow on a farm. If someone can come up with a percentage.. I will grind and mix these into a pellet. See what happens or I will do it after I build my chicken coop.  

Dave, have you pelletized any fish feed before?  how is your success at making it float?

Duckweed is a great ammonia sink but you are right, it takes a lot of space.  Now if you were to use a settling tank of some sort to catch the solids and use a net/degassing tank before sending the water to the duckweed beds you will probably not need to deal with all the waste from the fish.  If you remove the solids out to the soil gardens then you don't require as much plant bed to use up the minerals from the fish waste.

oh no - growing duckweed is the main idea.  i want all the ammonia to go to duckweed production, and just a tad of veggie growing space with whatever is left over.  i do plan on having 2 separate recirc systems.  one for the fish, with a bio filter and screen filter.  the filtered waste then goes to the duckweed loop, never to be seen again in the fish loop

Marty, not at all scientific, but my BSFL  eat pretty much whatever I feed them, in one day, so long as the feed rate is somewhat consistent. And I believe the wet conversion of waste is about 20%, meaning 100 lbs of goop in, 20 lbs of worms out. I'm sure the feedstock will influence that ratio, but it's a starting point.  If memory serves me, Dr. Olivier of the BioPod stated that he puts in 100 lbs of pig manure every day.  I know that regularly put a 5 gallon bucket of rabbit entrails into my bin, and it is gone the next day.  Gone. Only hair and bones remain after 24 hours. The fur becomes loose hair because the skin it was attached to is gone. Hope you weren't eating dinner

Oh John, I've seen some of the forums they have on BYAP with this--they've got pictures that make you want to either puke, or do it yourself. 

So, Eric, what you're saying is you want to see a picture? I can do that

Awesome! I have a strong stomach so of course, now I want to do it! 

floating food is not prefered by tilapia, usually.

Watch your fish as you fry, they prefer decay on the bottom, but learn to eat floating food.

Jon, that's a lot of rabbit entrails.  Are you selling rabbits?  We hunted them years ago and definitely shot too many of them a couple of times when it came time to clean them.  I've not seen BSF activity yet here at home in N. Fla and that surprises me.  I've cultivated BSF for three years now but never paid close attention to when I had larvae, exactly.  I'm ready to ramp up production this year.

Not really, George. We occasionally sell or give rabbits to folks, but primarily they are just another meat source for the family. We have 6-8 does and a buck, and they pop a dozen babies each every couple of months. The babies are about 4-5 lbs in 10 weeks. Quick math puts me conservatively at about 500 lbs of rabbit per year to butcher, or about 10 lbs per week. Of the 10, I'd guess about 6 or 7 of it is guts, fur, and bones, and 3-4 lbs of meat for the table. Not really sure about that, never measured. Anyway, that 6-7 lbs of guts translates to 1 1/2 pounds of BSFL grubs which directly feed the fish, resulting in a pound or so of fish. We have been slow about breeding them this year, too many projects 

http://aquaponicscommunity.com/group/arizona-aquaponics/forum/topic...

posted a couple more bsfl pics here, in a similar discussion, sort of