suite des échanges sur les les système "RAS" Le 04/10/2012 03:32, Warren A. Turner a écrit : Bonjour Badiane, Si les systèmes RAS sont tellement rentables, comment se fait-Asie ne produit pas de tilapia de cette façon? Le Vietnam a récemment produit 1 million de tonnes par an de poisson-chat Pangasius, rien à partir de systèmes RAS, pourquoi? Systèmes RAS sont utiles pour: 1) Produire des espèces de grande valeur dont une bonne maîtrise de l'environnement est nécessaire. 2) Produire du poisson où la biosécurité élevé est nécessaire - SPF crevettes, le barramundi en nurserie, etc 3) Production de poissons tropicaux dans les climats où la température de chauffage est un coût important et vice-versa sans doute, par exemple si vous voulez produire du saumon en Thaïlande au moyen de refroidisseurs. 4) Production de poissons où le foncier est très coûteux - comme dans une ville. 5) Produire du poisson dans les zones arides et où le sol n'est pas adapté pour les bassins, comme dans le désert. 6) Pour les aquariums publics.

Hi Badiane,

If RAS systems are so profitable, how come Asia doesn’t produce tilapia this way? Vietnam was recently producing 1 million tonnes per year of Pangasius catfish, none of it from RAS systems, why?

RAS systems are useful for:

1) Producing high value species in which good environmental control is required.

2) Producing fish where high biosecurity is required – SPF shrimp, barramundi nursing, etc.

3) Producing tropical fish in temperature climates where heating is a major cost and probably vice versa, for example if you wanted to produce salmon in Thailand using coolers.

4) Producing fish where land is very expensive – such as in a city.

5) Producing fish in arid areas and where soil is not suitable for ponds, such as in the desert.

6) For public aquariums.

There are many systems and many ways to raise fish. The one most suitable is the one that produces fish at the lowest cost per kg. If that cost is significantly lower than the present market price for that species, then it is a viable business.

To everyone - don’t be a lover or a hater, keep an open mind. All systems have their uses.

Best regards

Warren

*From:* sarnissa-african-aquaculture-bounces@lists.stir.ac.uk [mailto:sarnissa-african-aquaculture-bounces@lists.stir.ac.uk] *On Behalf Of *BADIANE ABDOUL *Sent:* Wednesday, October 03, 2012 6:05 PM *To:* sarnissa-african-aquaculture@lists.stir.ac.uk *Subject:* Re: [Sarnissa] Request for Technical Support!!

RAS is now essential for the development of aquaculture in Africa. ok the cost is high (energy, tech, food, etc...) but it is very profitable. So it's not small investors who will be able to build but only leading investors can afford to have.

With regard to the cost of production per kg for my case the RAS I head in Côte d'Ivoire, it is about 1000 f cfa (but the sale price is excellent) can be higher cages or ponds production. But how many production you can do in the year with the RAS while for cages or ponds you can do more than 2 harvests.

Our RAS have only 0.4 ha of growing and we produces 3,000 tonnes year. 0.4 ha of Pond cant do it.

Environment impact of RAS is less than cages or pondsfarms. The little water that comes out is treated and reused

The problem of the RAS in Africa is they have never been managed by capable people. Make fish farming would never mean that can handle a RAS it takes a high-tech

your post does not take into account many factors. Think that the RAS will not work in Africa is really stopped the development of this sector.

*BADIANE Abdoul Aziz Aquaculture Specialist /Consultant Supervisor production HydroFish *

06 BP 316 Abidjan 06 *Côte d' Ivoire* Tel: (+225) 22 40 25 12 Fax: (+225) 22 40 32 20 Mobil: (+225) 58 48 93 00

*De :* African Tilapia <africantilapia@gmail.com <mailto:africantilapia@gmail.com>> *À :* sarnissa-african-aquaculture@lists.stir.ac.uk <mailto:sarnissa-african-aquaculture@lists.stir.ac.uk> *Envoyé le :* Mercredi 3 octobre 2012 9h09 *Objet :* Re: [Sarnissa] Request for Technical Support!!

Dear All,

Well said Nick!

Many of the people selling such systems are technical sales people with little or no background in Aquaculture in Africa, and some simple calculations would show their systems are not competitive with traditional pond-based or cage-based production techniques. These RAS systems depend on reasonable cost grid power supplies, and in Africa obtaining these is expensive, and the supply is extremely unreliable. Back-up generators just add to the cost, and are often so poorly maintained that their reliability in an emergency situation is suspect.

Unfortunately these “white elephants” are not only giving RAS a bad name, but also (from an investment aspect) Aquaculture in general, and South African systems in particular an unsavory reputation.

While there is no doubt that RAS has a place in the overall scheme of things, most applications of these technologies are usually only cost-effective for tasks such as hatcheries and holding systems. In Africa, with such a wealth of still unexploited sites for gravity fed ponds and quality waterbodies for cages, it will be long time before RAS can produce fish at the same price.

Adrian Piers

Agriculture, Fisheries and Aquaculture Consulting

East African Community and SADC Region

Phone ++260 965 445464 (Zambia)

Email tilapia@zambia.co.zm <mailto:tilapia@zambia.co.zm>

*From:* sarnissa-african-aquaculture-bounces@lists.stir.ac.uk <mailto:sarnissa-african-aquaculture-bounces@lists.stir.ac.uk> [mailto:sarnissa-african-aquaculture-bounces@lists.stir.ac.uk] <mailto:[mailto:sarnissa-african-aquaculture-bounces@lists.stir.ac.uk]> *On Behalf Of *Nick James *Sent:* Tuesday, October 02, 2012 6:49 PM *To:* sarnissa-african-aquaculture@lists.stir.ac.uk <mailto:sarnissa-african-aquaculture@lists.stir.ac.uk> *Subject:* Re: [Sarnissa] Request for Technical Support!!

Dear Stephanus

I am intrigued to know the aquaculture credentials of the "South African Engineering company" that did the design of your project. Did they show you a working model of their design that was fully operational? If they did not, were they able to give you referral to an overseas or inter-African example of where their design parameters were working?

I ask because SA is getting a reputation for high-tech system designs that simply do not lead to profitably operational fish farms.

A 500 tonne/pa. tilapia farm is considerable in terms of production and infrastructure requirements...BUT it is the way that it is done that will make the difference between yet another white elephant...and a viable aquaculture unit. We are getting a little tired of these "engineer-designed" set-ups designed by people who have never kept a fish alive in their lives, as they are giving RAS aquaculture in Africa a bad name.

regards

Nick

Nicholas P E James Rivendell Hatchery PO Box 6146 Grahamstown 6141 South Africa Cell 082 575 9781

email nickjames@intekom.co.za <mailto:nickjames@intekom.co.za> WEBSITE http://www.rivendellhatchery.co.za/

----- Original Message -----

Dear William,

Allow me to take this opportunity to introduce my selves. I am Benedictus Stephanus from Namibia. We are battling to get an Fresh water Fish farm off the ground at the Naute Dam for the last 4years. Of the challenges we have are more of technical support base. Thus we are in need of a technical partner which could take care of the technical requirements of the project.

We look forward towards the valuable support from the forum at large.

Kindly,

Benedictus Stephanus Executive Chairman Naute Aqua Fish Farms cc Mobil: +265 856 095 352 Email: bstephanus@iway.na <mailto:bstephanus@iway.na>

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