Backyard Aquaponics
A place to discuss aquaponics

That's the way I do it. I researched ways to heat economically....never found a solution My small leanto will give me surplus heat which is blown into the house when it's sunny and above 35f. At night I feed a little heat into the leanto. If I had the money I would have built a 4 season sunroom with a french door to exchange heat. If I didn't live in a flood plain/high water table area I would have dug down 4 ft and built a stand alone GH.

My FT is in the basement so it doesn't freeze. Members told me it was too much head and not a good idea. You have to keep in mind that most members are in an arid climate. Their soil is poor and water is expensive. There are not many of them that have to deal with freezing temperatures.

Here is a good link to some solar ideas, subterranean heat and diy heaters.
http://www.builditsolar.com/Projects/Su ... se%20Plans

Thanks guys. Having the tank inside would have been the best choice, but unfortunately the GH is way to far away from the house. My next house, I will definitely have the GH next to the house for that reason. I will look at the solar heaters as well. Right now I just want to thaw everything out to get ready for the spring.

So I think might build one of these to keep it warmer in there.



It's made out of a 20lb propane tank.

So if I just circulate the water in the FT and have a small filtration tank, will that keep my bacteria alive for the spring?

Best info I have found from from one of my bookmarks. I just copied it fr you.

http://www.fishtanksandponds.co.uk/aqua ... teria.html



Oxygen

All nitrifying bacteria need a well oxygenated environment or nitrification will cease. Ideally the oxygen level needs to be above 3 mg/l (most fish need a dissolved oxygen level of 6 or 7 mg/l). If the environment is totally devoid of oxygen the bacteria will eventually die. The time an aquarium filter can be left off varies with temp. At cooler temps the metabolism of the bacteria slows down and so they will last longer. It also depends on the dissolved oxygen level of the water when the filter was turned off and whether the filters taps were closed or left open. Nitrifying bacteria will all die in the absence of dissolved oxygen after 24 hrs but it will take several hours to reach this point (longer at cooler temps) so if a filter has been turned off for a day or so it is worth restarting it and letting the remaining bacteria recover. Even if 90% have died filter bacteria will double their numbers every 24 hrs. Slow by bacteria standards but even with just 5% left the filter would recover in just 6 days.

Temperature:

Temperature plays an important role in the nitrification process. The optimum temp range for bacterial growth is around 30C depending on the scientific source used. Temperatures above and below this will inhibit nitrification to varying degrees.

Other important temperature to note are as follows:
1, 18C growth rate decreases by 50%
2, 9C growth rate decreases by 75%
3, 4C no growth occurs.
4, 0C and 49C nitrifying bacteria die

You will notice that at 18C the metabolism of the bacteria is halved. This is the likely temp of many cold water aquariums may drop to at night if they are not heated in some way. It is one of the main reasons why cold water aquaria should only be stocked at half the recommended level of their tropical counterparts.

Try Goggle nitrosomonas, biospira, nitrospira and nitrobacter, nitrification, freezing etc...

Rairdog, thanks for the info. I really do appreciate it. So I'm pretty much starting all over again, once I get everything thawed out.

I'm going to be better prepared for next winter for sure.

So I think I'm going to retro fit a RMH. So I'm going to have to have the combustion chamber outside of the GH, as I don't have room to put it inside. I will put the "mass" underneath my GB, that's the best that I can come up with at this point.

I was thinking originally to use the floor of the GH as my "mass" but I'm not sure if that would work very well. I still have a lot of reading up to do, but I think this will be my best solution for the winter.

What does everyone think? I would appreciate any advice. I'm bored waiting for spring!

I think the idea has potential if you can regulate the amount of heat well enough. You may have to work out some automatic delivery system for additional fuel to keep it going on really cold days. Might want to look at Web4Deb's thread or YouTube posts about his Rocket Mass Heater. There are some other RMH's on the site but I'm not remembering who has them at this point . Hopefully some of those people can chime in as well.

Web4Deb also setup a subterranean pipe system for heat storage and release early on. I believe it used 4" irrigation pipe to blow warm air underground for heat storage. This sort of system needs to be isolated from the surrounding soil for best results but if the greenhouse was just going to vent the heat anyway, this seems like it could keep some heat inside. Here's an example someone did - http://3x5aquaponics.blogspot.com/2011/06/subterranean-heating-and-cooling.html

Definitely still look into the solar heater as well.

Well from what I've read so far, and that isn't a whole lot yet, they are supposed to hold heat really well with a 2-3 hour burn. Now I don't know where these people live or what kind of temps they get in the winter.

I'm thinking if I can get away with running it a couple of times a day, morning and night, I would be able to stop things from freezing. Now all of that is speculation, but some heat is better then none at all.

I did find a video that shows one being done for a GH and they used the ground as the mass. This is what I thought of doing when I first saw a RMH. So I guess I can use the floor of the GH as my mass. I will have to do more reasurch of course. http://www.permies.com/t/2976/wood-burning-stoves/greenhouse-rocket-mass-heater-vid

I will check out the solar heater as well, as long as I have room to do it. I like the idea of the subterranean heating, but I'm not going to be able to do it for this GH, not enough room. I will put it on the list for the next one I build. I remember reading a post about doing this a while ago. I will have to look at it again.

I did read through a couple of RMH threads on this forum, but not Web4Deb's though. I will look for it and read though it.

His thread is definitely worth reading but it's probably faster to find the YouTube videos on the RMH by searching google for Rocket Mass Heater Web4Deb. This will give you an idea if you can use the information.

Yeah, I have been reading through his thread, and I've got to say, that is one impressive GH! I am just getting to the RMH stuff.

So this is what I think I'm going to do:



I'm going to have the RMH outside of the GH, simply because I have nowhere else to put it inside.



Then I'm going to run the pipes underground in the middle of the GH, using this as my mass, and vent it on the other side.

I'd probably do it the way you're suggesting but I might wish I had put the loop under the grow beds. I worked at a greenhouse where they used forced air heat and ran ventilation tubes directly under the benches to warm the root zone. Your greenhouse is looking great!

Cheers

Thanks Scotty, I still have a lot of work to do on it. I still need to get the twinwall polycabonat for the roof and walls. Right now I just have plastic sheeting on it to get me through the winter.



My fish tank is thawing out reallt well.



My sump is still frozen, but I don't think its frozon to the bottom, which is good for my pump.



That's a good point about keeping the mass under my GBs. So what if I use the whole underbelly of the GBs as the mass? Even to the point of including my drains as well. As long as it doesn't get too hot, which I don't think it will. I would have to be able to get at them in case of a problem. Very interesting

I'm not sure how much it will matter in a greenhouse that size since all the area will probably get heated. I just figured making it rise under the grow beds would warm those more than if it went straight to the ceiling.

I'm in the same boat as far as knowing if it will be too hot. You need to ask someone like Rob (Web4Deb) who's done this and explain what you want to try - then there is a chance he'll know what you need or be able to point out someone who does.

Cheers

Ok, thanks Scotty I will.

So I have another question, and I think I know the answer. I have to cover my GH and I was going to use twinwall to do it. Do I need to have it clear on the north side of the GH, or can I just cover that in wood? I think I'm ok coving it in wood, but just wanted others opinions.

In your climate I'd cover and insulate the North Wall pretty well. Because of the angle of the sun in the Winter, you can also do some temporary insulation for parts of the roof and end walls (might even be able to make it permanent part way up and along the ends like you see in some solar greenhouses). I have some styrofoam panels that fit tight between the verticals and roof sections - looks ugly but does help. Depending on the angle of your roof and the angle of the sun the panels can reflect additional light down to the bench level. Something like bubblewrap on the sides facing the light, unless it cuts out too much sunlight for you. The Twinwall is good and for looks you might skip the bubble wrap. Cover the inside tanks enough to keep condensation down but still allow air in to the tanks. I've always found the Spring and Fall periods were when I had the most condensation issues because of having to catch the transition where the problems start to occur.


In the Summer I replace some 3 of my lexan panels with bug screens (you'll need more removable panels with the larger greenhouse but it's still cheaper than fans and electric over the long haul). Just let the air flow provide ventilation (no fan except for air circulation in the Winter to keep condensation problems down). If you make at least some of your panels removable like this you can keep the door closed and some of the bugs out. Try to place these screen areas away from electrical outlets that you don't want to get rained on.

Hope this helps.

Ok, that's what I thought. That should save me some money, as I still have lots of wood

So the GH is designed to have 8 roof vents and I was going to make the sides open as well. I think that was your idea early on in this thread. I really liked the idea because I know that it will get really hot in there.



I will for sure insulate the wood parts and North wall and the far end. The end with the door does get afternoon sun, not sure how much that matters.