Backyard Aquaponics
A place to discuss aquaponics

If the max air temp is 30C, you should be able to keep them year round. I think it's when water temps get above 26C, they start struggling. Just make sure you have plenty of air-stones, and it should be alright.

I think my water got up to about 27° or 28°, can't quite remember, I was a while ago now. Is there any chance of them getting worms with a higher water temp? Or is that just an out in the wild thing?

I haven't heard of any worms in Aquaponic setups. It's usually more controlled environment then the wild.

If the water gets to 28C, it'll be a bit hot for the trout, but you can usually grow them to plate size in a season before you need to pull them out.

I don't know how fast tilapia grow. But heating AP systems is usually difficult, the grow beds suck in all the heat when it's hot out, and drops all the heat when it's cold.

In an aquarium, the heating is more efficient, because the water isn't flowing through the grow beds and picking up the heat/cold. Which is why I recommend finding a fish suited to your climate, rather than trying to make the climate suit your fish.

Edit...

What about catfish?

Ok thanks, that all makes sense. Trout are native to here, so I think I will try trout this year and see how it goes. If it goes bad I will try a differnt type of fish.

Both trout and talapia are fast growing, Id go for alternating seasonal species. Trout in winter and talapia in summer.

That's a good idea Charlie, the only problem is that my winter can get as cold as -20. Today it was -15. So I'm not sure how much growing I will be doing in the winter, I haven't tried it yet. I think, this year, I will stick with trout and see how it goes.

I was out there today, and the FT was frozen over and the sump as well. I have 1 lonely small mouth bass in the FT, and he is still alive.

My FT is in an un-heated basement so it doesn't freeze solid but has got down to 35f. I shut it down in Jan and Feb. Just don't feed the fish much and circulate on warm days to give them some oxygen. Little to no food.

For cool weather crops you can grow snow peas, spinach, lettuce, chard, broccoli, cabbage, pak choi and kohlrabi. I start the seedlings around late Jan or early Feb inside. When the water temp hits 45 to 50f the starts go in the beds. They grow VERY slow at this temp but survive. This is usually early to mid March. When the water temp hits 60 they perk up. At 65 they take off. 70 is probably optimal. Around mid May they are mostly harvested to make room for warm weather crops. Chard will last all season for me. Most others bolt. Go easy on the vinning/fruiting crops in a new system. They take of great but suck too many nutes and harvest can be disappointing. My system is small and I rely on the dirt garden for tomato's, bean, cucs, melons.

You can check out my thread below for some tips about cool weather AP. I ramble but it is a good place for me to document and refer to when determining plant start dates and how they progress. Very nice BTW.

Hey thanks for the info Rairdog, I will certainly check out your thread. I do get colder then you. Right now we are sitting at -15 (5f) so it might be more difficult for me, without some sort of heating, in the winter. Last year was my first go at it, that was my "proof of concept" if you will. I'm going to go at it full boar early spring, and see what happens.

I did have the water cycling well in to December, but someone unplugged the power to my pump without me knowing and everything drove up. I'm just hoping that my pump is still ok. It is located in the bottom of my sump, which is about 3 feet below the ground. There is ice on the service of the water, but I can't tell if it's frozen all the way to the bottom. My father-in-law thinks it will be ok, because it was submerged in water. I guess time will tell.

I'm zone 5. It was 9f this morning. There are in parts of Ontario that are zone 4. I would add about 2 weeks for that zone. We hit -17f last year but the basement gets supplemental heat from the duct work and remained just above freezing. I have never had it ice over. If I was in your situation I would drain the tanks in mid Dec. When water temps fall below 40f there is little to no nitrification. You are only providing oxygen to the fish by turning the water over. You can bypass the beds and just circulate the water to about 30f ...but it is a gamble with ice build up.

I just looked at a map and I'm in zone 5b. If I bypass my GBs, how does that effect my bacteria? Do you circulate the water to your GBs in the winter? If I shut the whole system down or bypass the GBs, how does that effect the age of my system? Or will I have to start it as a new system every year? Will I have to cycle the water every year as well?

I haven't finished going through your thread yet. Your GH looks good, I am going to put twinwall on mine as well. I need to wait until the spring though.

I can not believe that I have not seen this thread before today! I am supprised that you dont have any supplemental heating in your greenhouse. That would certainly prevent freezing. It would also be mandetory if you are going to grow out tilapia. Some people heat the water, but i believe heating tha air in the greenhouse instead prevents humidity problems.

Yeah, I haven't quite got to supplemental heating yet. The system is still a work in progress, although not right now it's too cold. I wasn't sure what I wanted to do for the winter, but I can't help but thinking that I want to keep it going all winter. Like you said, I will need heating of some sort to do this. I will see how the summer goes and decide in the fall.

I would have done things differently this year, if someone hadn't unplugg my pump, now I'm kind of stuck until the spring. I'm going to put a light on top of the FT to melt the ice so that I can get things running as soon as possible.

I don't think that I'm going to grow tilapia, I think I'm going to grow trout. I will just have to keep an eye on my temps in the middle of the summer.

You can buy a floating heater that is used for cattle watering troughs in the winter to get it thawed out from a farm supply store. Another trick is make sure your standpipes are removable. It there is a fitting that sticks up above bottom of bed drill a pin hole in it. Then you can completely drain the beds. I take a 5 gal bucket of HOT water from the house and pour it in the gravel guard to thaw out the drains. I just did mine a few minute ago. We are hitting close to 50f here the next few days so I have my pump back on. When we get low 20's I turn it back off. I have a bypass at the pump with spray bar so I can circulate without the beds to supply oxygen but I have gone up to a month without any circulation and the fish (bluegill) survived.

I still have never used any type of heater in GH. Believe me....I have searched for a few years for a cheap solution. It's just not cost prohibitive IMO. I am considering building a diy flow through water heater element to bump the water up 10-15f in the spring and fall. Plants grow much faster in at a water temp of 65 than 50. Youtube AP water heater. DavePilot (member here) has a nice video.

https://www.youtube.com/watch?v=YQ8vUUpwYgU

Ok, now that's pretty cool! I think I'm going to be building one of those. The temperature controller is really cool as well. I now have one on order!

Yeah I have seen those stock tank heaters before, I was using a light bulb because I have one already. I used to use that for and outdoor pond to keep it open over the winter. It actually works well.

Good air circulation helps with the humidity problems so I keep an oscillating fan going. If condensation forms on the ceiling it will drop cold water onto the plants and can cause lots of problems like mold and bacterial infections. An air heater also helps prevent condensation.

I use a floating stock tank de-icer heater in one system (RAS) and an air heater in the greenhouse (AP). The air heater is just a cheap space heater hooked to a Win100 plug in thermostat and all of this plugs into a GFCI socket. It's good to get a space heater with safety features like auto shut off if it gets knocked over. If you get much sunlight there you might be able to rig a solar air heater part of the year to help with warming the greenhouse, they are easy to build but might cause more temperature fluctuation than you want

This is the stock tank de-icer brand I'm using - http://www.kvsupply.com/ultimate-de-icer-500-watt?CAWELAID=983674187&CAGPSPN=pla&catargetid=320011160000087263&cadevice=c&gclid=COX968iw08MCFQWUfgodnp4A2Q
I haven't decided if I like them or not - the temp seems to run close to 50 most of the time in the IBC I'm using for my RAS system. The tank is partially enclosed but plenty of outside air can flow in (mild climate here). I think this brand comes on at a higher temp while most come on at freezing. The first one I had kept tripping the GFCI so I went to a lower wattage model and haven't had any more problems.

In the middle of Winter you probably don't get enough light to grow plants so you'll probably have to supplement if you want to do this. http://www.waldeneffect.org/blog/When_to_plant_for_a_winter_harvest/

I may have a couple more things to say but I have to get going.
Hope this helps