Backyard Aquaponics
A place to discuss aquaponics

My grandmother found this in a newspaper some time ago. It's an article about a privately-owned Dutch agriculture research centre that's researching aquaponics by order of four agri/horticulture companies. I've translated it for you guys.




"Growing tomatoes with the use of tilapia fish"

by Gert Onnink
Bleiswijk


It's the newest innovation in modern agriculture: using tilapia fish to help grow tomatoes.
Since March 2007 "(Green Q) Improvement Centre" in Bleiswijk is researching something remarkable.
"We use the fertilised waste water of the fish to water the tomatoes", says test leader Sjoerd Nieboer. "The innovative test uses about 5000 of the popular tropical Whitefish. In the same area, about 800 square meter, we grow tomatoes in a durable way. The big advantage is that the waste water of the fish isn't discarded, but it stays in the system for the tomatoes. The water is used twice, and the space is used twice", says Nieboer. "We use tilapia fish, fresh water fish that you can buy in the supermarket nowadays. The fish is not only good for raising, we can also use the excess heat from agriculture."
The test is being done by order of four horticulture companies and takes place in one of the eleven departments of the privately-owned research centre active since October 2006.
The taste of the tomatoes after the test is unknown.
"It's a project that's going to take multiple years."




It's funny how they say it's something new and innovative, while the basic principle of aquaponics has probably been around longer than I have. And apparantly I'm not the first Dutchman with an aquaponic system.

I just found their website; they even have an English version. You can find it here.
You can also see the trials per department (aquaponics in dep.1), and there are three pictures of the tilapia and the tomatoes in the news section.

On another website I found a PDF file with more information, but it's only available in Dutch (here). It tells schematically how the water is filtered and fed to the tomatoes. I translated this too:
1. The fish water is pumped to a belt filter
2. The water is filtered from big solids
3. A UV-scanner kills bacteria and virusses
4. The water is heated to the optimum temperature for the fish
5. "Biological life" in a trickle filter filters the water (I think they mean nitrobacter and such)
6. Sensors measure temperature and individual ions
7. The clean water is pumped back to the fish
8. Depending on how much the water is fertilised, it is partly pumped also to the tomatoes; it's stored in a tank together with the drainwater of the tomatoes
9. The water from 8 is pumped through a UV-disinfecter and stored in another tank
10. When needed, the tomatoes get water from the tank from 9, with the necessary nutrients that are still missing in the tank from 9 added
11. Fresh rainwater is added when the water level in the fish tanks falls because of the tomatoes using some of the water





Anyways, I live about an hour's drive from Bleiswijk. I think I'm going to contact them and ask if I can visit them some time. It's not going to be any time soon though, I'm very busy with uni

Tom, thats the first impression i got from it too. I'm well and trully sick of people making out that their company or research body or invention is researching a new and innovative technology called aquaponics.............please! LOL

Working on something 'new and innovative' will get you government grands

Today I read in the newspaper that this two-year research program has ended successfully.
They have a website now, and they even have an English version:
http://ecofutura.nl/indexuk.htm


They've also made a short film which they put on Youtube, which unfortunately is only available in Dutch.
http://www.youtube.com/watch?v=t9ke0GUk8aE

I translated it quickly (I hope it's readable!):
"In 2008 the two-year trial "Ecofutura" ended. During this project, the symbiosis of aquaculture and greenhouse production was researched on technical and economical feasibility. In the trial, the tilapia fish swim directly under the tomato plants, so they can use each others surplus optimally. Besides the fertiliser that the fish leave in the water, the CO2 that the fish produce can be directly absorbed into the plants. Furthermore, the space is also used twice. Feeding the fish is fully automated; the amount of fish food is monitored closely so the exact nutrient input can be calculated. The specially developed fish feed is the main source of minerals for both the fish and the tomatoes.

The solid fertiliser (fish poo?) and the leftover fish food are filtered out by rotating drum filter. These can be used outside the system as soil improver or in a fermentation plant.

The filtered water is disinfected using a UV-rays.

In a trickle filter, biological conversion of ammonia to nitrate takes place. Also, CO2 is removed from the water and O2 is added. A fan is installed on the top of the trickle filter tower to speed up this process.

An advanced computer is used to keep track of the fish tank. All measurements can be directly seen on the computer screen (........?).

The fish water is pumped to the technical room. This is where the water is mixed in the right ratios for the tomatoes.

During the Ecofutura project, the symbiosis has been tested on a small scale. After two years of research, it can be concluded that both the water and the residual heat from the greenhouse production can be used for aquaculture. In return, the fish provide minerals and CO2 back to the crop. The space is used in a smart way so that the fish can be efficiently merged with a greenhouse. That is why combined culture is economically and efficiently the best way to produce crops and sustainable fish. The result is tasty fish and vegetables.

The Ecofutura project is a collaboration between Aquaterra Nova, Green Q, Groen Agro Control and Priva."

Those are some good looking tomatoes! I love the way they roll up the vines as they grow longer.

I take it that the mechanical room is where they add nutrients to make the water perfect for tomatoes?

They seem to make it a bit more overly complex.

I've seen huge systems that are little more than lots and lots of tanks with fish or plants growing in them. About all the tech stuff is some water pumps and some air blowers. Filters being tanks or drums with shade cloth in them. Settling tanks with nothing in them that allow solids to settle so workers can clean them out regularly.

But the simple systems require more careful monitoring by people who know how to tell what needs adjusting.

Simple is better.

So what are they adding to the water for tomatoes? I think everyone here is able to grow tomatoes just fine in their systems without adding anything. Just curious what they have to add. I assume it is because they filter out the solids?

I'm not sure if they add anything at all! I think they store the water in those large tanks, measure the water values and mix them so the tomatoes always get the same amount of nutrients.

If they add anything at all, I think it's potassium and iron, and not nitrate. But maybe they add things like hormones as well?

Thank you for translating this into English. It is much appreciated.

I would like to know how they remove the sludge buildup on the tomato roots or perhaps there is enough aeration that it doesn't build up anerobic pockets, even though I'm sure that both the Tilapia and the tomatoes could deal with it. If they were growing more sensitive plants or fish, there might be a water quality issue. In addition, I think the Tilapia would eat the roots of other plants. Not much eats any part of a tomato plant.