Backyard Aquaponics
A place to discuss aquaponics

I reckon Toddscat is right - it IS a really catchy, easy to remember name... I can just imagine the fun you will have trying to create a jingle/ catchphrase for your ads too!

Follow your heart... If it feels right just go for it.

+1 S.C.O.R.E. is boring, and as long as you have Gardens in the name then I think it's great. There was a greenhouse place down the road called Mr. Natural's, would they have that name changed too?

Thanks for the name help, all.
I've spoken to all sorts of people, and have decided that fun and easy to remember trumps respectable. So I'll stay with Howling Moose Gardens.

Speaking of which, I'm 99% sure I've found my starting greenhouse. Since this will be the first (that I know of) greenhouse-based commercial AP system in Minnesota, I'm going to start by leasing space, and then once I've proven the concept (and have the financial numbers to prove it) I'll try to build a custom AP greenhouse with all the awesome passive/thermal sink stuff that has been discussed in the Temperate Climate Aquaponic Discussions and other threads.

So, here's the space:


On the north end are 6 greenhouses that run east/west, connected by an almost north/south running "head house". The three buildings running almost north/south on the south end of the complex are:

Left: concrete partially buried root cellar
Middle: greenhouse containing the loading dock and tractors etc.
Right: (biggest building in the complex) a metal fabrication shed

The fields to the west haven't been sprayed in 20 years and the landlord is willing to rent them out to veggie production (he's been haying it for the last few years). The scruffier space to the north of the greenhouses is space for potentially more greenhouses.

This is what the inside of the 6 east/west greenhouses look like:


They're 30'x96' (roughly 9m x 29m) = 2880 ft^2 (261m^2)
and are connected by this headhouse, which is 20' x 120' (6m x 36.5m)



The landlord is renting the 5 good greenhouses to someone else for 6-8 weeks for the spring seedlings (northern hemisphere, remember), and during that time I'll be in the loading dock space plus the smallest of the greenhouses, building my infrastructure and putting in a small raft system to cycle up.

Once the other guy is gone, I'll move into two of the 30x90' greenhouses, and expand from there as I can.

The place is 25 miles from my house, which is longer than I like to commute, but at the price this space is available for, I'll take it for a few years!

I'm unbelievably excited that this is finally coming together!

So jealous!

Looks like an awesome site.

Time to design my AP system for this location!

A reminder, each greenhouse bay looks like this:


(looking in from the headhouse towards the exhaust fan on the far end) and I have two that are side by side, with about 8' (2.4m) between them.

I'm doing mostly a trough/raft (DWC?) system, with gravel growbeds at the head of each trough to act as the solids filter. The concrete path down the center of the GH is 5' (1.5m) wide, and I'll run two 4' (1.2m) troughs down each side:

.
(not really to scale, specifically I think the FT is too small)

The greenhouse floors themselves slope towards the exhaust fan end ( ---> ) by about 1 degree, which probably isn't enough for me to simply lay the troughs on the dirt and get good flow (I'm told I need about 2 degrees).

I could build some of the low cost troughs like those in Hawai'i

which are essentially 2x4s held up by poles, and the liner stapled on. The weight is held by the ground.

But I think I want to insulate the troughs, which means I'll probably build them on plywood, with the insulation below in the frame, and along the sides, outside the liner.

But that means I'd need to create my slope, probably by bolting the plywood troughs to 4x4s, a la growing power:


(just the bottom layer, and only 12" (0.3m) deep).

The simplest way to do it, it seems, is to run the water from the FT to the gravel beds, and from there into the troughs, to flow to the far end ( -----> ) where I'd pump it back to the FT.

HOWEVER, it would save a TON of labor if I could pull the ready-to-harvest rafts out of the near end of the troughs, because they'll be processed in the headhouse.

So, I could just force the rafts up against the water flow, or I could reverse it so the highest end of the troughs is at the exhaust fan end of the greenhouse, and have the troughs flow towards the headhouse. (<----- )

I'd like to keep the fish tank near the head house, since that'll be the warmest area in the winter.

Should I move the FT to the cold end of the GH? Should I just run long pipes to the far end? That might end up needing a two-pump system.

And, another series of questions:
I can run pipes between the greenhouses, as long as I do it at about 8' (2.4m) above the ground. Should I have one fish tank per greenhouse, or build/buy a bigger one and pipe the fish water to both of the GHs? Bigger systems = more stable, of course, but would the extra electricity be worth it?
Along the same lines, since this system will be trough heavy, I'll probably add in extra aeration with a blower. One huge blower for both houses, or two smaller ones, one per greenhouse?

(I'll always have backup pumps and blowers...)

Can you not bury the pipes? 2.4M is a lot of head which means larger pumps.



Personally I would have a fish tank per greenhouse, but linked up together (with underground or on ground pipe) so it is one large/more stable system. I would still put a pump in each fish tank which gives you some redundancy also.

Alas, no. The GHs have doors I'll need to close, and the connecting headhouse has a concrete floor, and I can't tunnel under the GH walls.


Again, pipes can only connect in the air, above the GH doors. So unless I wanted to try to build a gigantic no flows overflow between the GHs, I'd need a pump to connect them.

I may be able to put in shallow trenches for pipes *within* each house, but nothing other than aerial connections between houses. :shrug:

nice space you have there!!! this is gonna be one hell of a system

can you utilise one BIG ft in the headhoue to feed each greenhouse,then sumps at the fan end?

Neatly through the walls is not an option?

Wow, this is interesting stuff....

I wouldn't worry about moving the plants against the flow of water in the channels, when the water comes out of the pipes into the big wide channel, the flow is barely discernible...

You don't need fall in raft channels, you need perfectly level, thats what ours are anyway. And yes, multiple small tanks is by far best. In our big system down the back that has 5000L tanks, next time I would put in multiple smaller tanks joined together for each system. perhaps 3 x 1500L tanks would be far better, then you can have an easier staggered crop, providing a more constant nutrient level.

a 1 degree slope over almost 100 feet would have a 1' fall i think.. you might want to divide the troughs into sections?

Why?

Whoops, never mind. I'd mis-read something. I agree with EB that the troughs should be nearly horizontal. I'll take a grade reading next time I'm out there, but it is 1 degree max across the entire length of the GH.

Ohh yeah! Start of a new commercial sized!

- No slope needed!
Water will level it self, and if you make a slope one end will stay dry. (Take a baking sheet, fill with water, make it slope, see whats happening.) Water will flow towards the draining point.

- I have no experiance with commerial systems, but making a row of standalone systems makes sence for me. If you have one big system, and you get a diseace -> you are out of business! I would thing one separete systems each GH. (maybe 2 systems / GH depends of sizes)

- "passive/thermal sink stuff"
The keys: insulation, sun and thermal mass.
What is the greenhouses covered with: Policarbonate or glass or plastic foil? You will most likely need to insulate north sides. Are the greenhouses insulated around in the ground?

How much sunlight do you get in the winter? What is the angle of the roofs? How much they shade each other?

The best thermal mass is water. As you are planning a DWC system, you will have plenty of it. This means if you have enough sun, enough insulation, than you dont need to use the earth as thermal mass! No pipes, no vents, saved money.

Rough calculation on thermal mass:

GH size: 30'x96' (roughly 9m x 29m) = 2880 ft^2 (261m^2)
Water needed for thermal mass: 5 gallons/ft^2 (http://aes.missouri.edu/bradford/education/solar-greenhouse/solar-greenhouse.php) -> 14 400 gallon needed

DWC systens 4x 25m x 1,2m x 0,3m = ~9 500 gallon (36 000 litre) / GH + 4x 500 gal sump + 3 000 gal fishtanks = 14 500 gal . This could be enough, but by raising the height of DWC to 0,5m with same sumps and FTs = 21 000 gal = 7,3 gallons/ft^2! You can even compensate the weaknesses of insulation!

Huge calculations needed here!

I subscribed!

If the greenhouses cant be insulated to a certain level, and you are not planing tropical fish, compost heating is still a solution, like growing power does it in all but one of their GHs.