Backyard Aquaponics
A place to discuss aquaponics

Time to go shopping... for larger cookware. Those are some nice looking fish!!!

Hi, I'm new on this forum but found your posts searching for 'Dutch', because I'm Dutch. We're experimenting with aquaponics in Amsterdam. Your thread reads like an exciting story and I think it's really inspiring!

I'm curious how your system is doing now, with these cold temperatures (temp varies between -1 and 7 deg Celcius). We've built an insulation tent around our systems and use aquarium heaters, but that's not really in the spirit of sustainable food production... We have big plans for the future, but right now this is what we can realize.

Did you build your rocket mass heater? Does it work? How's your system doing?

Groetjes,
Els

Hallo Els,

Nice to see some more Dutch enthousiasts!

Our system is now in a stage of very low activity. The greenhouse is not finished and the GB are exposed to the frost we have had during the night. The rocket mass heater is nearly finished, in my head. Not a single brick has been laid down though, time is something we seem to lack.

We still have three trout in the tank, which are showing no problems with watertemps of 4 degrees. Water heating is something I am not planning to do. We keep an eye on things and will spring into action when a cold patch of weather is predicted.

I have come across your aquaponics tower in the media a few times, I'd love to get some info on the specifications and design.

Keep Us Posted!

very nice

OK, we are heading into the unknown with regards to the operation of the system in freezing temps. This weekend's prediction is 10 degrees below zero during the nights with little above and below zero during the day. Currently there is only little frost during the nights, water is still approx 4 degrees.

Plants are slow but still steaming ahead. We have a couple of hardcore beans which are still with blossom and producing new fruit.

I presume that with constant flood we perhaps could avoid getting the cold air in the growbeds which could freeze the thin layer of water on the media. On the other hand, if we keep it on auto siphon, the bigger flow speeds may avoid freezing of the water all together. AiAi, choices.

PVC is not very happy in very low temps, it is also one of the minor concerns.

A lot of snow has been predicted as well, so I would like to predict that some scenic pictures will follow shortly.

Hi Hoeve,

Your beds should be ok for awhile just keep the water moving. I'm thinking CF without the siphons would be best and present the least amount of surface area to the cold weather and have less freezing but I'm not certain. It's likely you will still get water frozen on the growbed media along the surface either way (got to get that greenhouse and heater finished ).

Cheers

Well, we decided to change nothing, just take a chance to learn what would happen. As it turns out only the top layer of pebbles got frozen. The water as moving fast enough by siphon not to freeze up. The FT water temp dropped to minus 1 Celsius(time to recalibrate the thermometer?) without any icing. Trout was still swimming along, not too interested in the food though.

And yes, pictures;



A good feeling givver, bean still flowering;



A bit depressing, all slowly decaying old friends;




In any case reason to be satisfied, we have acquired the knowledge that short spells of medium frost are not to be feared.

"Frost" is what we get in Australia Lol. What uv got is natural refrigeration.

It has been a wonderful time this past year, but all things must end. Due to the persisting sub zero temps experienced and still expected we decided to pull the remaining three trout, drain the GB's and stop the pump. The FT water temp had already lowered to -2C and a total system failure because of ice blockage or damage was becoming closer and closer.

It has grown silent in our backyard.

We will begin cycling "a-new" in the spring.

Hoeve out.

I Expect to see an update around mid April!

Hoeve...
As a desert denizen, I can offer a couple of sideways fixes for your freezing temps, without resorting to fuel.

Out here, we go below ground to avoid the heat. I know you have water table issues, so try the reverse.

Insulate with straw bales, and then cover with dirt/ clay. 15" [sorry, no conversion] insulates to a stable temp... if you were to insulate your fish tank, pump, and the bottom of the grow beds. Your heat transfer won't be completely altered, but it may give you a longer growing season in the green house. I don't know where you are latitudinaly {not a word, but the only way I could think of it, now} and how much sun you are getting, but folks up in our snow country are using some of the techniques, and getting a thru winter growing season. If you can keep your water moving, you may have to switch your produce to 'winter produce' like broccoli & such. They tolerate both cooler temps and less sunlight.

Which direction are you facing? A southern exposure would give you a way to utilize daytime heat/solar exchange using large water bottles in the south that collect heat during the day, and radiate it back during dark hours.

The solar heating water is not connected to the system, simply generating stored heat during those hours sunlight is gone... a 'water battery.'

I'll endeavor to find the links, and get back to you.

We live at N 51 57 2, E 5 13 40.3

The sun exposure to our backyard is OK, the BY is in the NW direction. I have to admit the our GH is not yet totally finished and some big gaps can be found in places. The FT and ST are under an open lean-to, so we can still gain quite a lot if we closed this. I have been thinking about a thermal mass, but found the space in the GH too limited. We still have a rocket mass heater planned...
A solar heater on the roof of the lean-to could also be an option. But time is as scarce here as in most places.

It would be very nice to get the links, looking forward to it.

Thanks!

Hoeve Innedi, if you have not read zsazsa'a thread that will be a treasure trove of info for you

I have, and it has been!

We are Back!

Just got some Wels catfish fingerlings, and boy are they pretty! GB's are all seeded up and sprouting, it is a very nice start of the season!