Backyard Aquaponics
A place to discuss aquaponics

Hi everybody



I'm based in the Tarn in the south of France and am thinking about setting up a system here. I have an old textile factory of about 400 square meters but i'm not sure about the temperature swings. We can have 40 C in summer (sometimes more but only for a few days!) and as low as - 15C in winter obviously Tillapia would love the summer but impossible to keep the temp in the water in the winter, any body got any ideas that doesn't involve 40 euros a day for heating?
and is there anybody else local?

Welcome Seberdee,

Whether this will work for you kind of depends on your goals. Will this just be for yourself or are you planning on selling produce and fish?

If you find the right fish, you don't have to heat. It stays warmer where you are than it does where I am and part of my system is outdoors. I rarely have to heat but I keep the water temps just above freezing when it gets cold (last year it got to -12F or -24C which is unusual). Had to heat twice last year. Of course not much will grow and the fish aren't eating at these temps but there's no restarting the system in the Spring. You don't have to have the fish finish growing out in one season this way. Here in the US some type of sunfish, like bluegill would work for a family system over the Winter if you can keep the water from freezing.

Hope this helps

Hi Scotty,
The system will be for the family at the moment but hopefully if it works i will expand it to start selling vegetables. in the factory there are big channels cut in the floor that are just right for a sump tank they are 75 feet long about 5 feet wide and 3 feet deep in the middle and in another part i have an above ground concrete tank that was used to wash wool in thats about 100 feet long and 4 feet wide and 5 feet deep that would need cleaning and some sort of liner which would make a lovely fish tank, I cant see any other use for it and it seems a shame to just leave it sitting there.I have a stream running right past the outside of the factory that has rainbow trout in it but i think in an enclosed water system even a very large one the water temp would get to warm for trout we generally have 30C or 8 to 10 weeks in the summer.The only reason the trout in the stream survive is that it comes straight out of the mountains

Your climate seems a bit cooler than mine. We get -5c to -10c in a cold winter (haven't even seen close to that this year which is really odd) plus we often get +30c in the summer and occaisionally +45c. What I found is that the summer temps are not too bad because we have clear cool nights so that heat gained during the day can be lost at night.

During your summer do you have clear skies and cool nights or does it stay warm over night? If it cools down at night then there is a real good chance you can keep trout all year round.

Regarding you factory...

Factories don't tend to make good greenhouses. They just don't get enough light and often you can not remove the roof without compromising the structural integrity of the structure. Many roofs use the roof skin as a structural element to stiffen and strengthen the roof. If the roof is tile or slate this will not be the case but even with the roof replaced the beams and rafters create a lot of shade which will slow down your plants.

Unless of course you add electric lights which it sounds like you are sensibly not going to want to do because of the expense.

What I would do...

Greenhouse.

Investigate getting a second hand Green House. I don't know about poly houses but here is Australia professional growers are out competing small poly house growers so there are lots of poly tunnels standing around naked and empty. Also in the Netherlands they are pulling down a lot of previous generation greenhouses and glass houses to replace them with new ones. There is nothing wrong with them just that they can get better production from the new fangled high tech ones and since land is so expensive the old ones are getting replaced.

System

Go for a big system, for a backyard system anyway. ~10,000L FT 20,000L of GBs and sump to suit. That system will provide more than enough fish and large part of your veg for your family and give your surplusses during the year that you can prevserve, sell or swap. Also the large volume of water will be very unlikely to get too hot because of its thermal mass.

Fish
I'd start off with trout at the end of summer and feed them almost as much as they will eat so that they are ready for harvest coming up to Christmas. If the water gets too hot eat them but as long as you give them lots of O2/air they should be fine up to water temps of 25-26c (they might not be because australian rainbow trout may have become adapted to warmer temps, but I don't think so since bits of france get rather warm too). If you find that you can not keep trout all year round then check out English perch I mean Eurasian Perch They can tolerate much warmer water but they are not as easy to grow and they don't grow as fast as rainbow trout.

http://www.bim.ie/media/bim/content/publications/corporate-other-publications/thumbnails/bimno_24_Farming_of_Eurasian_Perch_Volume_1_Juvenile_production.pdf