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GSDbreeder
05-26-2011, 10:04 PM
I wanted to start an Aquaponics system that would be able to produce enough Tilapia to feed my family and make raw dog food for 10 German Shepherds and any puppies that come along throughout the year.

From what I have read so far... The Tilapia can be fed crush prawn and vegetables. The Prawn would feed off the waste of the Tilapia. The Vegetables would gain the nutrients from the Tilapia and Prawn. Do I understand that right?

My dogs are fed over 400lbs of dog food each month. Atleast 21% has to be protien or 24% for pregnant mothers and their children. The Tilapia would be the source of their protien and vegetables would be the fill in. I don't want to stock up on fish food, so I thought throwing in Prawn would solve that problem. This system would also be able to breed the fish and Prawn also, so I can have a continous supply. I plan on building this in a green house using solar power as my only source of power. I work at a power plant and have to deal with water chemistry so the water chemistry shouldn't be an issue. I am still trying to figure out a way I can maintain chemistry without having to buy chemicals for the system.

I enjoyed Big Als setup, but I think I am gonna have to go a bit farther because of my goals.

My biggest question..... Can it be done?

I hate doing math, but I need to come up with a system which will provide these minimal factors...

I must be able to produce 125lbs of Tilapia each month once I get the cycle going. 25% protien

I must be able to produce enough Prawn to feed the Tilapia and fingerlings. I know their diet will not be strictly Prawn, but left over vegetables has well.

I need a growth pool for fingerlings, hatching tank, breeding tank and adult tank (4 total) Haven't figured out the sizes yet, but was hoping to get some ideas here.

The Prawn will be able to share a tank (preferable not round for footprint purposes) with floaters(lettuce or someother type). I know they are territorial so screens seperating them will also have to be used. I will probably need another tank to remove the Prego prawn to hatch the young. From what I read... the hatching tank for the prawn is brackish, so I wouldn't be able to grow anything else in them, is this correct? Now I am up to 6 tanks.

The Process....

The Tilapia tanks will be drawn from bottom (fishy poo) then ran into the Prawn tanks(fish poo food).
The Prawn tanks will over flow into a sump continously. (7 tanks now argh)
From sump.... the rest will be pump into the rest of the garden that has river pebbles
Then back to the Tilapia tanks to start the cycle all over again.

I kinda have a deal going with a local farmer. I buy a Steer each year and he raises him, them I slaughter him for 600+lbs of beef. This usually last me for a year for a family of four. The dogs don't get the beef. I really want to be set up to provide my food without having to depend on anyone. I live on 30+ acres with a few ponds and 50,000 acres of gamelands surrounding me.

What would you guys suggest for tank sizes? and if you have any ideas to make this work would be greatly appreciated.

Big Al
05-27-2011, 05:07 AM
hi there GSDbreeder, thank's for the mention, glad you enjoyed. from what ive read prawn like shrimp
prefer a rectangular type of tank with a taper built into the bottom. prawn's are very territorial so you
wont be over stocking them unlike shrimp. best of luck with your set-up. best wishes. good luck Big Al

keith_r
05-27-2011, 05:59 AM
where are you located? for good tilapia growth, you want the water temps in the mid 80's... you may be able to grow some of the food for your tilapia, like duckweed and veggie scraps, but to get decent growth, you need a high quality fish feed..
if you have good conditions, you should be able to grow the fish out to a pound in 6 to 8 months.. so 125 fish a month..
are you planning gravel growbeds? that would provide your filtration, but if you're thinking of DWC, you'll need prefiltration so that you're not pumping solids through the roots..
are your ponds spring fed? what are you raising in your ponds? RAS might be a better option for growing that much fish

JCO
05-27-2011, 06:48 AM
I don't want to rain on your parade, however I think you are out on a limb thinking that you can raise prawn in the numbers you will need in order to produce the amount of food the Tilapia will need.

Figure out the number of Tilapia you will have to produce each month considering at least a 6 month grow out period for the Tilapia (don't forget the prawn grow out also) and I think you will see what I mean.

Don't forget, you are wanting to produce food for you and your family also and that means even more Tilapia to produce each day/week/month/year. You will also probably tire of eating fish every meal, I know I did.

As for your dogs, my wife and I have raised about everything you can think of. Back in the 70s & 80s we owned a horse ranch in Southeast Missouri in the foothills of the Ozarks. We raised registered Appaloosa horses and owned some powerful named breeding stock but was never quite able to make them actually pay for their own up keep what with vet bills, upkeep of the pastures (fertilizers etc.) and Oh.... don't forget the feed especially in the winter. Takes a lot of quality hay and sweet feed to keep the bellies of a Stud horse, 12 mares and 15 colts and yearlings full every day of the week not to mention wading the snow and mud twice a day in freezing weather or smothering heat in the summer to get it done.

We sold out and moved to Florida in 1987 and since we have been here we have raised exotic birds; Sun Conures, African Greys, Love Birds, Cockatiels & Parakeets. Dogs; Miniature Schnauzers, Dachshunds, Yorkshire Terriers & Lhasas. Cats; Munchkins & Bengals. None ever produced the amount of return expected or hoped for considering the amount of work and initial investment involved.

I now raise KOI just for the love of them for as I have found in the past in order to raise anything in sufficient numbers to hopefully make it self-supporting, it's a full time job, takes a lot of space and specialized equipment and takes a lot of money to get the operation started and maintained and a lot of specialized marketing to sell the results.

I had over a million dollars invested in our horse ranch including the horses and it still wasn't enough to produce the kind of return that I needed just to be self-sustaining (able for me and my wife to quit our full time jobs) or show a return on the amount invested worth talking about.

As for your dogs, are they truly paying their own way or are they just an expensive hobby as I have found in the past right up to and including my Appaloosas which I loved dearly. My wife and I were both working full time jobs in addition to the horse ranch. You and your wife try getting up a 4 AM (every morning) any morning in the winter with a foot of snow on the ground, temperature of 5 below zero with a wind chill factor of 15 below and now both of you go out and spend an hour or more tending to the horses, then come back in and get ready for work. I can't speak to cold weather like Jackalope can with his Wyoming winters but I know what it was like for us in Missouri and it sucked hind tit all the way..! :shock: :o

So I guess what I am saying is if you want your family to be completely self-sustaining, you are going to have to evaluate what you are willing to give up to get there...dogs (wife.. kids :lol: ) or what you are willing to do and invest in order to get there.

I don't want to discourage you by any means, however the Aquaponics operation you are talking about is going to require at least or maybe more than a 30' X 100' greenhouse with heat (if you are going to raise Tilapia year round) and ventilation, lots of electric and considerable know how on the Aquaponics side. Notice I didn't say it couldn't be done.

I can't do it for you, but I will be glad to answer all the question you have that I can.

ALSO, Please go to your profile and put in the city and state where you live, there may be members close by. :mrgreen:

urbanfarmer
05-27-2011, 06:54 AM
I'm no expert on the prawn, but I believe they don't actually eat the fish poop only pick through it for undigested food. Also, that sounds like it would create a water quality problem for the prawn. I might be mistaken, but I think they are fairly sensitive to the quality of the water.

Since you only want the prawn as fish food for the Tilapia, how about replacing that portion of your concept with Duckweed, Black Soldier Fly Larva, Red Wiggler Worms, and Algae (with all the zooplankton it would attract). This would be easier and give the Tilapia a wide range of diet to keep them healthy and growing.

Also, you can consider just setting up a few ponds with "green water" (pea green soup of algae) and then putting the Tilapia fry in there. Depending on your weather conditions (where do you live?) you can grow out fish very easily and with less maintenance. The only problem with this is you will need a way to control the population after the first season or so because it will get pretty crowded (they reproduce like rabbits). You might be able to just add a few predatory fish to control their population as well. Draining the pond is another option or having a big net sit in the pond is even yet another option.

There are many choices and it's definitely something you can do. You just have to figure out what works best for you and your geographic area and how much time and money you care to put into it.

TCLynx
05-27-2011, 07:10 AM
It kinda sounds like you are trying to raise tilapia in a closed system but you are planning on taking stuff out of that system to feed your dogs and family and hence the system is not truly closed and you will need to put some input in to replace what you are taking out. I think you have lots of research to do. I would suggest getting a small system up and running to help you learn while you continue the research into the bigger all inclusive systems.

You have not told us your location or climate so it is hard to know how feasible this is.

A note about duckweed. You need a huge amount of space to grow a huge amount of duckweed. 12 tilapia will quickly (5 days or less) clear the surface of a 16 foot by 2.5 foot duckweed tank and think you are starving them but add a hand full of high quality commercial fish feed pellets a day and they hardly touch the duckweed.

Seeing as you have a large amount of land, have you thought about diversifying a bit? Like maybe having some animals that will work to feed themselves rather than requiring you to build systems to feed them? Like Chickens and Muscovy ducks that could live in the woods and provide eggs and meat while largely feeding themselves free range if you have appropriate space and numbers?

Work on some food forest planting on your land as well to provide for you.

Back to the tilapia, to grow at the really fast rates that everyone likes to tout, they need really warm water 80-86 F is optimum (unfortunately this is a bit warm for many of the easy raft bed plants to grow.) Also, if you want tilapia to grow out big fast, you need to keep them from breeding. Commercial operations do this by raising all male stock (done either by feeding the fry hormone laced feed to make them all develop as males or by having special breeding fish that will only produce male offspring.) Smaller operations might manage by manually checking the gender of the fish when they are big enough but this is very labor intensive and prone to errors. In my aquaponics system I kept mixed gender blue tilapia in a cage in the system so they could not access the bottom of the tank and therefore couldn't successfully breed (they are mouth brooders so the female has to pick up the fertilized eggs in her mouth in order for them to hatch successfully so if they fall through the cage and she can't get them then no successful breeding.) Now with the cage culture I managed to avoid most of the problems though the females don't grow nearly as fast or big as the males I still managed ok but there are challenges to feeding in a cage (feed floats out of cage.) But this might be the best bet if you don't want to mess with hormone laced feeds or buying really $$ breeding colony fish or having to handle the fish so often for sexing and keeping them separated and stuff.

Now for growing tilapia out big and fast you really need to feed high quality high protein feed while they are young, this may be challenging if you are trying to produce all the feed in the system with duckweed and prawns. Also, even growing them out once they are big enough for the normal 32-36% protein feed for the more mature fish is going to be hard trying to do it on a system with no external inputs. Even green water culture uses fertilizers to get the algae blooms (I don't recommend this in an aquaponics system but there are other methods like solar algae ponds that might be of interest to you.)

Anyway, is it possible, well just about anything is possible, the questions are, what sort of resources do you have to make it happen. Choices of do you want really fast fish growth, then you probably need to use commercial feeds or is it more important to minimize outside inputs and grow your own feeds, well then the question is how much space and time and resources do you have to devote to this or will you reduce the amount you expect to get out of it. Finally the climate or size of the greenhouse will have a big effect on how possible this is and if you are in a cooler climate, how much can you put into heating that greenhouse? If you can't easily keep the greenhouse warm through winter, tilapia might not be the best choice of fish.

rfeiller
05-27-2011, 09:55 AM
Raising fish commercially for the tropical fish industry, I had to maIntain a certain #of each size of fish from number of spawns required, tanks seperating weekly age groups all the way to adults. It was totally graphed out. To make it truely a dependable source you sill need several times the amount if tanks and containers to control productivity and accelerated growth that you need than you have mentioned. Graph it out and you will understand what I am saying. If you crowd or mixed age groups it will cause stunted growth and cannibalism

JCO
05-27-2011, 12:01 PM
TCLynx, he lives in North Carolina somewhere...however if he is surrounded by national forest, it's very rural and to raise chickens and ducks in that setting is a chore. They have to be locked up securely at night and even then sometimes they aren't safe.

When I first moved to my horse ranch in Missouri in the foothills of the Ozarks from having lived in close to town, I had chickens and ducks (crested Khaki Campbell Ducks...beautiful ducks). The chickens... I had no problem in getting them to roost in the hen house, however once the ducks discovered the pond on the property, you couldn't get them to come back to the barn yard and within a matter of a few weeks the Coyotes and Fox and no telling what other critters had devastated my duck flock to extinction.

I live in an urban area now and still had trouble with predictors killing my chickens even though they were secured each night. Never found out what is was, tred trapping to no avail...wasn't happy about it, but finally got rid of the chickens.

With that in mind, it would take some serious thought as to what else could be safely raised in the setting this member lives in. :mrgreen:

rfeiller
05-27-2011, 03:00 PM
Rabbits are the easiest to contain and produce the best manure for earthworms. combination of rabbit manure and alfalfa a winng combination.

TCLynx
05-27-2011, 04:04 PM
I've been using electric netting to protect my birds but I've probably not contended with anything worse than raccoon or possum.

JCO
05-27-2011, 06:48 PM
I've had no contact with Coyotes here in Fl., however I can tell you from seeing it with my own eyes, a Southeast Missouri Coyote can lope up to a 6' fence and clear it in full stride without touching it or loosing his stride. There use to be a $25. bounty on their hides in Missouri back in the early 70s and I hunted them rigorously because the country at that time was overrun with them.

They were quick, clever and not easily caught with their guard down. That's when I used my Remington model 700 BDL 22-250 rifle... 6 X 18 Redfield scope with adjustable parallax and Uncle Sam's benevolent training to take them out at 500 yds. without fail and always from downwind. I especially like hunting them in the winter when there was snow on the ground.

However it looks as though I have highjacked this thread. Sorry... I'm not following my own rules... now back to the regularly scheduled program....rabbits would be a better choice providing you can build the cages critter proof. :mrgreen:

rfeiller
05-27-2011, 07:49 PM
Tilapia are certainly the fish of choice, can't have them here and it would cost too much to maintain.

TCLynx
05-27-2011, 08:10 PM
tilapia are not my fish of choice. I prefer fish that will survive my local climate without requiring heating to keep them alive (let alone eating or growing.)

I've found that in my systems the catfish grew just as fast or faster than the mixed gender blue tilapia and the catfish grew much larger. (easier to clean one catfish instead of 4 tilapia for a meal.) Anyway, now I'm growing some bluegill so I'll be able to compare their growth rates to the tilapia, if any of them are big enough to eat by December then I'll count them just as fast as my tilapia had been.

Only drawbacks is catfish and bluegill are not that interested in eating lettuce scraps.

rfeiller
05-27-2011, 08:50 PM
yup the idea was to have a complete system, using the veggie scrapes to feed the tilapia along with the prawns once you raise any other fish you have an expensive food bill.

TCLynx
05-28-2011, 05:20 AM
Well there are other things you can raise as fish food, like BSF larva, worms, crickets. In outdoor tanks/system I use bug lights over the tank to provide supplemental food as well.

rfeiller
05-28-2011, 07:36 AM
i have koi and goldfish, i will supplement the feeding with worms when the worm buckets are built up enough. it would be easier if they were primarily herbivorious. heating the water is what the "cost to much to maintain" statement in my previous post was about. I can't maintain the gold fish at the level of polution that tilapia can exist at either. i started loosing koi and 6" goldfish when the nitrates hit about 200ppm in 1000 gal vat. did a 50% water change trying to save the remaining ones. it weakened them to the point that they have broken down. catfish are tough, but i don't eat them. i am thinking about going with blue gill. the nutrient level in the vat only hit a little over 500 on the conductivity meter not the 2000ms suggested in backyard systems.

urbanfarmer
05-28-2011, 07:46 AM
i have koi and goldfish, i will supplement the feeding with worms when the worm buckets are built up enough. it would be easier if they were primarily herbivorious. heating the water is what the "cost to much to maintain" statement in my previous post was about. I can't maintain the gold fish at the level of polution that tilapia can exist at either. i started loosing koi and 6" goldfish when the nitrates hit about 200ppm in 1000 gal vat. did a 50% water change trying to save the remaining ones. it weakened them to the point that they have broken down. catfish are tough, but i don't eat them. i am thinking about going with blue gill. the nutrient level in the vat only hit a little over 500 on the conductivity meter not the 2000ms suggested in backyard systems.
200 PPM nitrate??? I had goldfish at over 1000 PPM nitrate with no noticeable signs of distress. They were like this for about 3 months. They were young though, but I bought the feeder comet goldfish from the pet store. At the pet store, they keep the water quality pretty low so the ones that survive are tough. I guess it's Darwinism. I still have these guys today and they are all over 6" in size. Some have even reproduced. I examined one yesterday and he was producing milt.

I'm honestly not sure though if my fish have strong genetics for surviving high ammonia, nitrite, and nitrate levels or if nitrate itself is just not toxic. The fish I am talking about were bombarded with urine on a daily basis. Ammonia and nitrite were spiked through the roof and so was the nitrate. I WAS trying to kill them. Only 1 died out of 40 in a 10 gallon tank. No water changes. To this day I think the feeder comet goldfish are the toughest fish, tougher than tilapia, but again it could have just been because they are kept in poor conditions and only the toughest survive...

TCLynx
05-28-2011, 08:38 AM
Nitrates as measured by an aquarium test kit are generally not very toxic to fish unless you are talking a really high level for a really long time. RAS often has 500 ppm of nitrates since it costs them money to change out water so they only do the minimum.

If you are talking ppm of nutrient like measured with a hydoponic meter (EC, CF or TDS) well those are actually measuring the electrical conductivity of the water and they are only estimating nutrient strength based on the conductivity of the salts involved in hydroponic nutrients and those meters have very limited usefulness in aquaponics. My system (unless I've lately added sodium chloride to deal with moving fish or a fish disease)
will usually measure about 0.4-0.6 on the EC scale of my bluelab truncheon which corresponds to 200-300 ppm with the ECx500 ppm scale or it would be 4-6 on the CF scale which is 280-420 on the ECx700 ppm scale. What does all this mean? pretty much nothing, just means there is still a tiny bit of salt in the system like 0.2 ppt.

After adding salt to the system to like 3 ppt because of say an outbreak of illness in the fish or getting new fish to add to the system, that truncheon is going to read off the scale and I would have to water down a sample by 50% in order to get an accurate reading that I could then multiply by two which if it were hydroponic nutrient and I had that reading all the plants would be dead (as well as the fish) and if we were talking hydroponics and I got the low normal reading, I might as well be running plain water. but this isn't hydroponics.

Anyway, I know of people who have had all sorts of types of fish in a system with really high nitrates. My nitrates have run well over 200 ppm (like I was having to dilute samples to get an accurate reading and then multiply to know how high my nitrates were, up around 400 at times and the catfish survived great. The ammonia and nitrites were kept below readable levels and my pH was high which I suspect is why my plants were not as good at using up the nutrients and I had high nitrates, even then the EC meter would tell me a low number unless I had salted the system.

cedarswamp
05-28-2011, 10:41 AM
1000 PPM nitrate and you call the pet stores water quality low? :lol: jk




i have koi and goldfish, i will supplement the feeding with worms when the worm buckets are built up enough. it would be easier if they were primarily herbivorious. heating the water is what the "cost to much to maintain" statement in my previous post was about. I can't maintain the gold fish at the level of polution that tilapia can exist at either. i started loosing koi and 6" goldfish when the nitrates hit about 200ppm in 1000 gal vat. did a 50% water change trying to save the remaining ones. it weakened them to the point that they have broken down. catfish are tough, but i don't eat them. i am thinking about going with blue gill. the nutrient level in the vat only hit a little over 500 on the conductivity meter not the 2000ms suggested in backyard systems.
200 PPM nitrate??? I had goldfish at over 1000 PPM nitrate with no noticeable signs of distress. They were like this for about 3 months. They were young though, but I bought the feeder comet goldfish from the pet store. At the pet store, they keep the water quality pretty low so the ones that survive are tough. I guess it's Darwinism. I still have these guys today and they are all over 6" in size. Some have even reproduced. I examined one yesterday and he was producing milt.

I'm honestly not sure though if my fish have strong genetics for surviving high ammonia, nitrite, and nitrate levels or if nitrate itself is just not toxic. The fish I am talking about were bombarded with urine on a daily basis. Ammonia and nitrite were spiked through the roof and so was the nitrate. I WAS trying to kill them. Only 1 died out of 40 in a 10 gallon tank. No water changes. To this day I think the feeder comet goldfish are the toughest fish, tougher than tilapia, but again it could have just been because they are kept in poor conditions and only the toughest survive...

rfeiller
05-28-2011, 12:36 PM
the reference to the conductivity of 2000 is what is stated in the "backyard and hobbyist systems" article in this website. it is the standard for hydroponics. i know salt increases conductivity. i was just puzzled at 200ppm nitrates and conductivity of a little over 500 with a target of 2000 in aquaponics according to the article, assuming that it was the target for aquaponics.

TCLynx
05-28-2011, 01:28 PM
Sorry I don't know that article.

urbanfarmer
05-28-2011, 03:26 PM
Oh boy... the conductivity of water is the conductivity of water... sticking electrodes into a sample or your main system will likely give you a pretty poor number at best. You would want to sterilize and filter sediment out of the water. Organic matter can easily affect the conductivity reading. Okay, assuming you've done this then what? The EC reading is not particularly useful because you have no idea what went into the water. So many chemicals (including byproducts and metabolites) can affect the EC of water you can not draw any real assumptions of the chemical makeup of the water from 1 number. To put it bluntly, it's just plain impossible.

AND, I still say nitrate is non-toxic to fish. :lol: :lol: :lol:

I had a thought on the stunted growth some of you have mentioned in association with higher nitrate levels. Did you know nitrate can turn back into nitrite? Ya, under certain water quality conditions this can happen quite readily. We all agree nitrite stunts fish growth (and of course kill them). Perhaps there's your real explanation??? :ugeek:

urbanfarmer
05-28-2011, 03:31 PM
Slightly off topic, but related to the "tough" fish... I just had a Tilapia fingerling fall 2 stores into dirt and I took my time in saving his stupid little butt... I put him back in water and he's swimming it off... I have yet to see a goldfish do this, but I think it would definitely be the ultimate fish challenge...

TCLynx
05-28-2011, 03:34 PM
Definitely, under really high nitrate conditions and in situations where low oxygen levels might exist somewhere in the system, you can get what is called de-nitrification and the first step of that is the nitrate turning back into nitrite. Some pond and koi systems use this on purpose since they don't have enough plants to use up all the nitrates and they want to avoid nitrate build up but the second step is pretty important, you have to get the nitrite to degass into the air as nitrogen gas, other wise you just wind up with nitrite problems in the system. So unless you are running baki showers or something similar, you want to avoid the low oxygen situations that might cause nitrate to turn back into nitrite.

rfeiller
05-28-2011, 04:54 PM
Setting up denitrification systems were at one point during the reef wet dry hay day the big deal. It took awhile to figure out that denitrification was being performed by the corals without our help. It was a very slow tricky anerobic process.

badflash
05-28-2011, 05:11 PM
Nitrate levels are not a problem with tilapia until they get well over 200 ppm. Some fish are more sensitive, but most cichlids are not. I know this from personal experience.

JCO
05-28-2011, 07:11 PM
OK, everyone including myself has jumped on the bandwagon here to show off our expertise, however the member "GSDbreeder" who started this thread has disappeared. Are you still with us GSDbreeder or have we dumbfounded you and caused you to loose interest? :mrgreen:

TCLynx
05-29-2011, 06:10 AM
Probably busy doing research into the myriad of things we have mentioned for his monumental project.

It is a pretty major undertaking. In the mean time I hope he gets a "backyard" scale system going that can help teach him what he will need to know.

JCO
06-06-2011, 06:43 PM
OK, it's beginning to look like I was correct...I PM'ed GSDbreeder and also sent him a regular email with no response to either. I guess we completely overwhelmed him or he found another forum with more helpful members.. :shock: :mrgreen:

rfeiller
06-07-2011, 08:43 AM
I Have to quit hyjacking threads.
What he wanted to accomplish in fish production alone requires a good size operation. I wish him well. Don't know what life would be without a German shepherd by my side.

tnguyen6914
11-22-2011, 11:06 AM
Hello everyone! I am new to aquaponics. Haven't started anything yet but planning to this spring. I found the prawn information quite interesting so I did a little more research and found this link

http://www.phoenixpermaculture.org/foru ... ith-shrimp (http://www.phoenixpermaculture.org/forum/topics/aquaponics-with-shrimp)

i havn't read through all of it yet but got excited so i'm posting it anyways! there's an image of a shrimpcage that looks like it might work! if anyone has had any luck with raising prawns with tilapia, I would love to hear more about it. happy holidays!