Meeting with university professor

hawaiinewbie

Hey Rupe, yah, now you can see how I am so confused with what he's doing and claiming.
He has not yet published his results. I'm not sure when he will. When he presents his data its pretty convincing. They guy did A LOT of experimenting.

I ran the numbers and at 30x30 yards thats 242 tables at 48 heads every month he's producing about 140,000 heads of lettuce a year. Maybe with fish sales he can hit 200000? You're right that 300000 sounds a bit high. Although a 3-4 pound tilapia here in Hawaii goes for 20 bucks a fish. So its might be possible. One thing to remember is he's doing this through the university so a lot of overhead costs are not factored in.

Rupe it also should be noted he modeled his system after hydroponics. He started there because he knew hydro works, then worked to integrate fish into the system.

When I get a chance I'll scan and post the manual he gave me.

Good conversation here. I like it!

novaris

hawaiinewbie wrote:

I don't understand your last statement about real working systems novaris.

I mean for backyard systems, ones that produce everything from root vegetables to banana's. If you base a system on his design you run the risk of being successful with lettuce

I have found that worms in the grow bed tend to produce healthier plants, as I understand it the worm casting have many components that are beneficial to the growth of plants, components that are not produced by the bacteria.

One of the problems with academics is when they extend their results in a generalisation. They refine a design for a specific purposes i.e lettuce and then generalise that as the "Best system". In the real world this usually falls flat on its face. You will also find that over the last decade or so many systems have been tried by people like members of this forum, when they share their experiences you have an evolutionary system. What tends to stick is what tends to work, we may not always understand why it works but we know it does.

hawaiinewbie

Ahh I see Noravis. I'm with you on your thinking. The professor is smart enough to know he didn't create the best system, only that he created a system that is viable, easy and efficient for growing lettuce and fish. His goal was to help island communities produce large amounts of food with little land and resources. He has helped island communities in the (Samoa, malaysia) pacific develop systems to feed the people. He accomplished this goal and then some.

If you wanted to grow a variety of veggies then his system is not the best. If you want to grow lettuce then I can't imagine a cheaper and easier one. A system that produces 48 heads of lettuce in 5-6 weeks costs $250 bucks.

I am anxious to see how well he grows other veggies.

King Erik the 14th

RupertofOZ wrote:

Actually... thinking about it... if we take trout @ 100gms... and a six month grow out to 800gms..

That's a 8x weight gain in 24 weeks...

If you were to use this example, start at 100g, double in size every 6 weeks, harvest at 6 months (week 24) then the fish would weigh 1.6kg at harvest. Thats a 16x weight gain. Must be some hormones involved somewhere?

While some of the figures seem a bit fishy, I'd be interested to hear a bit more about what the Prof has to say. What's the chance of getting him onto the forum to join in the conversation? If not, I'm sure he'd have some pics or tidbits of info that could be posted or a link to somewhere.

RupertofOZ

Haven't had the chance to work it out yet... but my gut feel tells me that for the same area... plants and fish... that the UVI floating raft system would out-perform....

hawaiinewbie

YEah crunching the numbers would be interesting. The professor did say that the reason he did this research is because the UVI system is, he felt, flawed and he felt it could be done better. UVI is productive but takes a lot of educated labor to run and energy to run the filter system. He said he didn't like it because of its complexity. Again, he wanted a model that could be utilized in underdeveloped village settings. Even if the UVI system out performs, you have to acknowledge the practicality of it.

earthbound

hawaiinewbie wrote:

Even if the UVI system out performs, you have to acknowledge the practicality of it.

Got to see something to acknowledge first...

Stuart Chignell

King Erik the 14th wrote:

RupertofOZ wrote:

Actually... thinking about it... if we take trout @ 100gms... and a six month grow out to 800gms..

That's a 8x weight gain in 24 weeks...

If you were to use this example, start at 100g, double in size every 6 weeks, harvest at 6 months (week 24) then the fish would weigh 1.6kg at harvest. Thats a 16x weight gain. Must be some hormones involved somewhere?

I don't have the details but a guy up the road from me is trying to get an experimental marine system off the ground (anyone like to contribute $200,000 or part thereof). He is planning on growing Seaweed, Polycheet Worms, Sea Urchins and Kingfish. The exciting part from my point of view is that they are experimenting with growing KF in low saline or even fresh water. Considering that the Kingfish can grow from 8-50g to 1.5kg in 6 to 8 months they could become a favorite in many systems.

gemmell

Stuart Chignell wrote:

I don't have the details but a guy up the road from me is trying to get an experimental marine system off the ground (anyone like to contribute $200,000 or part thereof). He is planning on growing Seaweed, Polycheet Worms, Sea Urchins and Kingfish. The exciting part from my point of view is that they are experimenting with growing KF in low saline or even fresh water. Considering that the Kingfish can grow from 8-50g to 1.5kg in 6 to 8 months they could become a favorite in many systems.

Holy shitballs batman, that's a good growth rate. The legal size limit for a Kingfish taken from the wild is 65cm or larger - they're a ridiculously good sport fish too. That would be awesome. Hook me up when he's got it going =) Inland seafood has been a dream of mine for a while.

RupertofOZ

gemmell wrote:

Stuart Chignell wrote:

I don't have the details but a guy up the road from me is trying to get an experimental marine system off the ground (anyone like to contribute $200,000 or part thereof). He is planning on growing Seaweed, Polycheet Worms, Sea Urchins and Kingfish. The exciting part from my point of view is that they are experimenting with growing KF in low saline or even fresh water. Considering that the Kingfish can grow from 8-50g to 1.5kg in 6 to 8 months they could become a favorite in many systems.

Holy shitballs batman, that's a good growth rate. The legal size limit for a Kingfish taken from the wild is 65cm or larger - they're a ridiculously good sport fish too. That would be awesome. Hook me up when he's got it going =) Inland seafood has been a dream of mine for a while.

Yeah they can grow fast in optimal conditions...

Quote:

Yellowtail kingfish have an excellent growth rate at higher temperatures, in intensive culture in tropical to sub-tropical conditions they can grow at least 1.5 kg and possibly up to 2.5 kg within 12 months. The food conversion ratio (FCR) for the species is largely unknown but likely to be reasonably good. The FCR for closely related species has been reported at 2:1 to 2.5:1 on a dry to wet basis. Growth rates will be faster at higher temperatures.

Attributes for culture
● There are existing producers of fingerlings for production.
● Yellowtail kingfish have fast growth rates in good conditions grown with good management
practises.
● There is an existing domestic market and export potential.
● There is potential for selling fingerlings to other growers
● Yellowtail kingfish is highly regarded for fresh consumption in Japan (sushi and sashimi) with
high farm gate prices
● Is a relatively hardy fish when past larval stage
● Adjusts well to sea cage culture, a technology well developed and known in Australia.

Issues or problems for culture
● High dissolved oxygen levels are required to be maintained constantly.
● There is a general lack of scientific and farming knowledge for this species, however culture
and biology can be related to Japanese culture of Yellowtail Seriola quinqueradiata and
other related overseas species.
● Issues such as disease, pests, on winter temperatures, optimum feeds etc and their effects
on culture are relatively unknown.
● Hatchery supply is limited requiring an improvement in reliability and volume of production.

They have also been known to have significant disease problems though, particularly in sea cage farms... whether or not this also applies to RAS systems.... :dontknow:

Also known to suffer deformity rates over 10% prior to first stage grading...

And Jaw malformations are a continuing problem in the production of Yellowtail Kingfish and can effect up to 50% of cultured fish.

Backyard Aquaponics A place to discuss aquaponics

Meeting with university professor

Backyard Aquaponics
A place to discuss aquaponics