Comment

Comment by TCLynx on November 12, 2012 at 6:41am

Well, I know when wild and farmed catfish are compared the farmed stuff has really poor omega 3:6 ratios compared to the wild fish.  Same goes for tilapia on commercial pellet feed.  It is only in the past decade or so that people have really paid more attention to such things and the animal feed industry has definitely not caught up at least here in the US with commercial fish feeds for warm water omnivorous fish.  (Now if you want to get grain free or GMO free dog food, well that is easier than getting GMO free people food but that is a whole other conversation.)

I can't really comment much on the feeds for the predator or cold water fish since I've not paid much attention to that being in a sub tropical climate as I am.

The fact that people are willing to eat farmed fish even with its less than healthy Omega ratios is kinda beside the point of wanting to make it better.  People still eat factory farmed eggs, confined feeding operation birds and feed lot beef, that doesn't mean they are all that good, people are just willing to buy what is cheapest still.

Of course those growing tilapia probably realize that if you feed the tilapia too often, they simply poop the extra feed out without even bothering to digest it much so with those fish, I suppose you could affect the nutrient levels considerably in a system based on the feed, I'm still not interested in growing tilapia much through except as chicken treats maybe.

Comment by RupertofOZ on November 12, 2012 at 6:11am

Ok... lets be more specific.. and a bit more scientific...

Many species, and indeed different growth stages... have different and specific protein, fat.. and most particularly... amino acid profile requirements.

Most species, or groups of species have what's known as a "limiting" amino acid...

i.e no matter what the level of other amino acids might be in the feed.... they will not be taken up (proportionally) beyond the maximum of the limiting amino acid...

 

And the feeds are formulated accordingly.. with required trace element provisions.. for each species group...

And actual anaysis of fish wastes consistantly show that other than phosphorus... very little trace elements are excreted.. they almost all taken up by the fish...

Luckily.. most AP system grow plants that thrive on nitrogen and phosphorus... and with constant replenishment of scarce trace element input from fish wastes, some benefit from worm action recycling within the grow beds... and supplementation by Maxicrop, pH buffers and chelated iron....

We can grow everything successfully in backyard aquaponic systems...

Commercially however.... I think it's another story... and the current baloney about nutrient profiles being hawked around... is just that... baloney... especially when related to seasonal water temperatures and feed rates... and actual water analysis...

 

Comment by RupertofOZ on November 12, 2012 at 5:58am

Marty, most fish feed formulations have specific omega3 & omega 6 components...

And you missed the point... 70% of the fish we eat.. is farmed... and totally acceptable to people...

I'd wager that most people couldn't tell the difference betweena "wild" fish.. and a "farmed" fish.. in a blind test...

I've given some of my homegrown trout... the an avid and club competition winning (for years in a row) trout fisherman.. and he said that they were "as good as anything he had ever caught in the wild"...

I'd also be prepared to wager.. that given the polluted nature of many of the wild fishery areas... that the health benefits of farmed fish.. would probably outwiegh the value of wild fish...

 

As to raising fish commercially on a small scale... and the profitability... well sometimes size is important.. especially in a commercial context....

But there are many, many small scale pond, and RAS operations.. that are profitable... or at least have been to date...

But yep... raising small volume numbers of low value fish... like Tilapia... probably isn't worthwhile...

Comment by TCLynx on November 12, 2012 at 5:54am

Before a spitting match begins, you are all right.

The commercial feeds have been heavily developed to grow fish as fast and inexpensively as possible.  Therefor, especially for catfish and tilapia, the corn and soy component of the feed is really high and therefor the Omega ratios are terrible from a health and inflammation point of view.  (same holds true for beef fed on grain instead of grass.)

And Mathew and Rupert both have good points.  There isn't much profit left over from standard food fish commercial fish farming.  Rupert is also still correct that the commercial fish feeds have been studied to make sure you can grow out the fish in the least amount of time possible and those feeds seem to provide a good balance of nutrients for the veggies as well.

And it is also true that online forums don't seem to be much help to people trying to figure out how to grow their own balanced fish feeds.  I'm not sure we should expect them to be that much help seeing as testing different feed elements and combinations to find the right feeds to make a balanced diet for fish is a bit more complex that simply looking up a recipe online.  And I expect if some one does figure it out as part of their commercial venture, they will have put considerable investment into that development and they should want to recoup some of that investment by selling either the feed itself or the book or information or systems to do it.

I did read a freshwater aquaculture book that had a section on growing feed supplement for fish but none of the ideas they talked about were really scaled up to provide more than an occasional snack to a modest amount of fish so simply developing systems to grow the feed on a scale big enough to even feed a backyard aquaponics system would likely be a huge en devour.

And I expect that is why there isn't a whole lot of help on the forums telling people how to grow/prepare a complete fish diet at home for fish living in tanks (because most people don't actually know how to do it, they just have some ideas for supplements.)  And if people are also trying to grow their veggies at the same time, an incomplete diet for the fish would also be throwing in the additional variable of incomplete nutrients for the plants.

Comment by marty lininger on November 12, 2012 at 5:36am

Rupert

not so fast.  fish feed is made to grow fish the fastest but that does not mean that the end product is the healthiest for the consumer.   it is well known amongst the health conscious community that farmed fish are not as good for you as wild specimens of the same species.  Omega - 3 vs Omega-6 being easy to define. the key is the feed with other factors like water quality weighing in also.

your comments   " ...duckweed, BSF.. and other things can be helpful, cheap supplements... but the are not substitute... or anywhere near complete feeds... even in combinations..."  fall right in line with most of the others here.  if you are correct, then there is no point in trying to raise fish commercially on a small scale because the profit margin is so small. 

Comment by RupertofOZ on November 12, 2012 at 5:18am

@Marty... you comments regarding commercial fish feeds.. are completely unfounded.. and untrue...

Most commercial fish feeds have been carefully researched, formulated to specific species... over nearly a century...

To provide optimal growth rates and fish health...

Commercial aquaculture is predicated on feeds being exactly so...

 

The reason you've probably found little support for home made fish feeds on the forum.. is precisely because most people are totally unaware of specific species requirements.. for specific growth stages.. and growth rates...

Whereas commercial aquaculture has spent millions of dollars in do exactly that.. in order to have a successful industry...

 

Duckweed, BSF.. and other things can be helpful, cheap supplements... but the are not substitute... or anywhere near complete feeds... even in combinations...

 

I'm not saying it's impossible... with the right knowledge, understanding... resources and money... to do it...

 

It's just easier and cheaper to just buy a product.. even with it's current unsustainable limitations... than to reinvent the wheel...

 

Over 70% of all the worlds consumed fish product.... is supplied by aquaculture... fed by commercial feeds...

Comment by RupertofOZ on November 12, 2012 at 5:07am

Anyone who claims to have a fool proof method to use to create a successful business if you just follow their methods, well, they using that on you, they are taking your money but I don't think you can expect what they sell you to let you do the same thing, at least not for long.

 TCL... isn't that exactly what is, and has occurred in the "commercialisation" of aquaponics...

Specific models based in specific climates/locations... being proposed as a "follow this plan/model... and you'll be successful" ... anyone can do it...

And more recently... follow this totally new (cough)... and completely uproven to have any commercial benefits model... anyone can do it...

Regardless of marketability/profitabilitiy of fish species/climate/location...

Comment by marty lininger on November 12, 2012 at 5:03am

Matthew makes an excellent point.  commercial feed is very expensive.

fingerlings are very expensive also. you need to make your own of both.

 beyond that, commercial feed produces low quality fish (to eat).  Omega-3 are low and Omega-6 are high in commercial feed fish.  fish are not meant to eat soy and corn, etc.  a diet more similar to the fish' natural feed will produce a better product, albeit not as fast.  finding a way to make your own feed is key, i believe.  there is not a great deal of info out there about making your own feed on a large scale. 

  if you filter your water mechanically and are willing to forgo the normally accepted greenhouse products side of the aquaculture (grow fish feed, not people feed), you can possibly use the fish waste to grow duckweed, and other fish feeds.  You must  learn lots about duckweed.  you need other sources of protein also.

i am looking into all these things myself.  i have found little support on this forum for this subject, most will tell you you should use commercial feed for various reasons.  however, most on this forum are not raising fish to sell, but raising fish to fertilize their plants.

  my efforts are on hold for now, hope to get back to work on my own commercial fish farm (small scale) next summer.

Comment by marty lininger on November 12, 2012 at 4:38am

Comment by matthew ferrell on November 12, 2012 at 4:19am

Catfish farmers make somewhere in the market of .01-.03 profit per pound.  That is why very few of the little guys are left.  Feed prices have more than double in the last decade as corn and soybean prices went up.  What most of you are going to find is that most small scale growers have to grow high value low output animals.  Like aquarium fish.  And like Chris mention, they do not want competition, but not because of uncle sam, but rather to keep there product high enough in cost that they can survive as a business on he low volume of production they have.

• ‹ Previous
• 1
• …
• 5
• 6
• 7
• 8
• 9
• …
• 14
• Next ›
• Page