The Future of Fish Farming May Be Indoors | Hacker News Reader

The Future of Fish Farming May Be Indoors

scientificamerican.com

65 pointsextarial33 comments

I'm passing this along from Michael Timmons mentioned in the article, a former professor of mine.

"""

Hello everyone (I was quoted in the article). The use of the term 'indoor' is actually not relevant. A RAS can be located indoors or outdoors. The key on the RAS is that the water is recycled (in a loop) that returns 99% of the water to the system instead of discharging the water from the system into a receiving body of water (or sewer system). Placing indoors in a 'cold' environment is beneficial for heat loss control.

HOpe that helps.

MBT (Cornell Univ)

"""

I'm confused why this keeps saying indoor, when it just seems to be talking about a more modern "raceway" system that has been used since at least the 80's, that I know of. Everything it described sounds exactly like the farm my dad used to run, except inside. The "indoors" part just sounds like a more expensive way to do raceways and probably isn't needed in most cases.

Can anyone explain the difference? Or is "indoor" just a buzzword here?

I'm all for more fish farming. Raceways are extremely efficient. During harvest season we were harvesting around 30,000lbs of hyrbid striped bass every 2 weeks off half an acre, with just my dad running the farm and me helping with the grunt work. We also had a few of the unused raceways dedicated to Tilapia as a side income, which were basically self sustaining and just needed to be fed. They bred faster than we harvested them.

I'm guessing the implication of "indoor" is that is it climate-controlled, and external variations of outdoors are reduced entirely or as much as possible.

I'm yet to learn about fish but I know the binary difference of "outdoor" and "indoor" when it comes to crop farming.

The article suggests that the difference is the water recirculation - that the "waste" water is cleaned rather than being removed. Is that how your farm's raceway worked?

Yes, it was cycled back through and filtered (through sand and plastic I believe) before being re-pumped back into the system from a retaining pond, then supplemented by a ground water pump to account for evaporation or other loss. Oxygen was pumped in separately from liquid oxygen tanks.

Disclaimer in case there are any more questions... this is about as far as my knowledge goes on this. lol I'm sure it was much more complicated than what I understand.

What were the economics of that operation? Cost, profit (or loss), time required to operate it?

I know they were high, but I'm not sure about the actual numbers. I just carried fish food and packaged fish. My dad did everything else. I think cost of the fingerlings (post-fry juvenile fish) were the biggest thing that cut into the profits.

> Water in RAS tanks flows through a bubbling container called a bio-filter, in which bacteria consume fish urine and convert it into a form of nitrogen that is safe for the fish and environment

I wonder if a system like this might be instead kept clean (in part or full) with the help of an Aquaponics[0] system. In that design, you filter the water by growing food hydroponically. The fish waste acts as a nutrient for the plants, which clean the water for the fish. Food out of both ends of the equation.

[0]https://en.wikipedia.org/wiki/Aquaponics

They seem to be combining several steps here (though maybe I'm wrong). In a comparable aquarium build the bubbling helps to oxygenate the water and to support the protein skimmer. You have things like bioballs with a large surface area to contain the bacteria and that acts to process the waste.

But, to answer your question: I think it can probably be done on an industrial scale. Many larger fish tank setups have refugiums, where the water is processed. Some people set those up with plants which, in my experience, grow really well. I've only used underwater plants, but it makes sense that you could use others.

I find animal farming fascinating because they are basically just miniature bio-factories - converting feed and other additives into a higher-value food product. Of course, each different animal converts feed at a different rate of efficiency and over a different timeframe, in different controlled environmental conditions.

I think there is a huge appetite out there for tasty, cheap, nutritious food. Fast food mega-companies are ignoring a huge opportunity here - imagine if McDonalds (or equivalent) was a food choice your could healthily eat for every meal? They would be better off thinking as their food as part of daily nutrition, instead of a meal out. They could adjust their operations and menus accordingly - with a significant increase in revenue.

>Tasty, cheap, nutritious

Pick two.

You can have the full pack here also. Tasty and nutritious are subjective terms in any case. The definition of cheap depends a lot on the zone. The same food can be very cheap in a country and a delicacy in other. Offer and demand.

When you put plants through an animal to concentrate the nutrients, you're going to get 10% efficiency. In these controlled systems, if you care about efficiency, it's always better to eat the plants. (https://en.wikipedia.org/wiki/Trophic_level).

Salmon are predators making the '100 kilograms of fish feed' line misleading. We basically feed fish to fish.

Resulting in a fraction more fish we like at the cost of vast amounts of fish we like less.

ex: "Freshwater feeds contain 45–54 percent protein and 16–24 percent lipid." http://www.fao.org/fishery/affris/species-profiles/atlantic-...

I would have been interesting to hear more about ideas for how to feed the fish. I think a lot of the fish feed today is from land based agriculture which is not very sustainable.

There has been experiments with using bio reactors to grow algae based food instead.

Actually, a lot of fish feed is made from fish meal, arguably even less sustainable than ag. The best solution I've seen is raising insects like black soldier flies on waste.

The use of black soldier flies larva could be a sustainable way. The larva are fed with organic waste, then use as feed https://www.youtube.com/watch?v=5M6u9ZX5ecE

Replace indoors by closed and you'll have it. Complex systems to maintain at long term, but we are learning still.

Sad. The future should be sustainable lab-grown fish meat.

That is what the future of any food production is. Organic and traditional food production is terrible for the environment because it consumes far too much land. We are destroying far too much wildlife to produce food using traditional methods.

Indoor food production either as mentioned here or as in bio reactors and hydroponics systems use something like 100-700 times less land for the same food production.

Think how much land could be given back to nature if we use these more efficient methods and managed to stabilize our population growth.

Forests and fields could be populated by wild animals again.

I share the same desire, but since we put price tags on land, it would be a tremendous effort to collect funds to buy land back and most people just don't have the incentive to make that happen. It's just a fantasy.

The value of land would go down if food production shifted elsewhere.

In general, it's the current-time value of perpetual production in a particular use, multiplied by the likelihood the land would be put to that use in the future.

So if International Paper owns a square mile currently used for fast-growing trees, the value of the land is the value of the next lumber harvest, discounted over the amount of time left until it's ready, plus the harvest after that, discounted by even more time, and so on, forever. Then you add the value from a developer that thinks, "this plot is really close to Townsburg, and I could build houses here that would get annexed". So you add the value of the land as residential housing, times the probability IP would sell to the builder.

It's the same for food. Most farmland is rather far away from anywhere people might want to build houses. The few houses that exist nearby are only there because the people that live there need to be closer to the open land than the cities. So if it stops being useful for growing food, it's value drops to the next-best use, which is probably not housing. One of those uses might be preserved wildlife habitat. It all depends on where it is, and what it's next to, and the perceived value of a particular use.

Or better still, just get the nutrition you need from plants. There's nothing essential in fish you can't get from plant sources, with a much lower environmental footprint.

And before somebody jumps in to say Omega-3, not only can you easily get that from plants but fish also get it from algae. They don't produce it themselves.

>Or better still, just get the nutrition you need from plants.

How about Vitamin B12? This article:

https://en.wikipedia.org/wiki/Vitamin_B12

says: "There are no naturally-occurring notable vegetable dietary sources of the vitamin, so vegans and vegetarians are advised[5][6] to take a supplement or fortified foods."

There is also this part:

https://en.wikipedia.org/wiki/Vitamin_B12#Plants_and_algae

but who eats much algae, among vegetarians? Wonder if Spirulina is one of those algae. Need to check. Spirulina as a food supplement is commonly available in capsule form.

B12 is produced by bacteria and we used to get plenty of it from the environment. Public sanitation means we don't have those bacteria in our food and water anymore so you need to supplement.

A lot of meat is also artificially enriched with B12 though and a lot of meat eaters are also deficient so a B12 supplement is probably a good idea for most people anyway.

It's added to all soy milk, far as I know, so personally I've never had to worry about that, I get B12 with my breakfast cereal.

Along with a huge amount of phytoestrogens from your soy juice :-/

I didn't remember hearing about those; you say that like it's Bad, well, dark innuendo at least, beerlord.

A lil while googling about them seemed to say no-one's sure what good or bad effects they have, if any. And they're in a lot of things:

"According to one study...foods with the highest relative phytoestrogen content were nuts and oilseeds, followed by soy products, cereals and breads, legumes, meat products, ...vegetables, fruits, alcoholic, and nonalcoholic beverages."

And well, Japan has the world's greatest life expectancy doesn't it? And they have soy everything.

Nowhere near the amount of estrogens you get from drinking milk meant for a baby cow.

That saying prefer almond milk myself.

Hmm with this talk of 'lab-grown meat', is lab-grown human meat going to be a thing? (OK, it needs a better marketing term. 'Cow meat' isn't great either. Well, 'long pig' wasn't bad..)

Whenever I ask that, my friends say there's something wrong with me. Glad to know that I'm not alone.

Hehe well I won't be joining you, I'm vegan, and even have a shirt with EATING PEOPLE IS WRONG on it.

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