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LFCummins
11th December 2009, 12:09 AM
I have been searching for plant beds for my system. I am in north Texas. Prefer 3'x6' or 4'x8'. So far ive found some in Wisconsin, California and Washington. The shipping costs are out of site making them too costly. Was hoping someone could link a source closer to me.

I could build but am unsure of the constuction, what materials might be required, due to the weight of the water. If some one has constructed their own beds and stand who might have a set of details it would be appreciated.

Thanks all

LFCummins
11th December 2009, 10:54 PM
It was suggested I use GARF's designer when I build beds.
It says 3/4" plywood. I won't be putting in the Acrylic

Material = Plywood w/ Acrylic
Tank Height = 16"
Tank Width = 48"
Tank Length = 96 "
Plywood w/ Acrylic Thickness = 3/4"
Approximate Gallons = 319

I am concerned - If the beds are 8 feet long and 16" high won't it bulge in the centers without support, specially at the top?

I had after thoughts of frameing it with 2x4's adding extieror paneling on the outside, then drillling a hole in each cavity between the studs and filling with expanding foam isulation. Cold is problem here in winter even with a greenhouse. As I said juss and after thought

nwestwood
12th December 2009, 08:00 AM
I used a 2x12 topped with another 2x4 for the side walls on my 4x8 foot DWC tank and used extra bracing on the corners and the joints. It's full of 12" of water and has no bulge at all. The base is 1/2 plywood on a solid wood frame.

pictures here http://www.utahap.com/Utah_Aquaponic_System_Construction.htm

GaryD
12th December 2009, 08:12 AM
Hi LFC,

Here's some ideas for the fabrication of grow beds:

Formply for the base - don't know what it's called in the US but it's what they use to make concreting formwork - it's more waterproof than regular plywood - and it's about 3/4" thick.
You can use formply for the sides, too. They can be anything from 150mm to 300mm deep. No point going any deeper than that for most purposes. If you want to prevent bowing of the sides (only likely if you use gravel as media), you can create a flange of formply - about 2" would be plenty.
You can also use timber for the sides - I've used the same wood that they use for door frames - about 8" by 1.5" - these don't bow under any circumstances.
Paint the structure to protect it from the elements and to make it look nice.
To line the growbeds, buy some plastic like they use on greenhouses. It's fairly thick and it often comes with a 3 year warranty against UV degradation.
Fold the plastic liner neatly into the grow bed and secure it around the top of the sides with some light wood and some screws or nails.
Insert a bulkhead fitting (picture below) into the bottom of the grow bed. Cut the hole for the bulkhead fitting using a holesaw. Take care not to allow the holesaw to chew up the plastic liner while cutting the hole.
Support your grow beds on concrete blocks - in Australia, we call them Besser blocks.
Grow beds like these can be used for a variety of growing systems. They are robust enough to fill with gravel (if you have a young back) and they will also serve as raft tanks if you want to go that way.

We use a small one 4' x 4' as a square foot bed and it has performed flawlessly for over two years so far. We'll be converting it to a wicking worm bed in the coming months.

I hope this helps.

Gary

LFCummins
12th December 2009, 09:26 AM
Thanks GaryD, Nwestwood

Will use 12" (300mm) high sides, for all my Plantbeds, I believe a resonable estimate will be $150-$200 complete for a 4'x8'x1' PB insulated on bottom and all sides. You didn't address the insulation idea, what do you think?

"Formply" im still looking for the equivlant here - It may be the MDO plywood, I think its a synthic composite or something thats designed for decks and extieror walls - some that im seeing have 10 year life.
Is this what you were suggesting ?

For stands I will use Cinder Blocks @ 1.48 each they seem to be be the cheapest solution. As you stated.

The Valve you linked in the pic - Does that go center of bed or is it prefferable to be opposite the water input ?

Again thanks for the information and suggestions.

PS - I am somewhat close to my bed design, I will draft enginnering drawings in Microstation or Autocad /scan completed plans and post - after I've run threw an attempted construction. Will include pricing for all materials and cut lists. With step by step instructions. If your interested

GaryD
12th December 2009, 01:23 PM
Hi LFC,


Will use 12" (300mm) high sides, for all my Plantbeds, I believe a resonable estimate will be $150-$200 complete for a 4'x8'x1' PB insulated on bottom and all sides. You didn't address the insulation idea, what do you think?

Timber seems to be much cheaper in the US than here.....so 12" x 2" like that used by Neal sounds good for the sides. As for the insulation.....I'm not sure what circumstances would justify it.


"Formply" im still looking for the equivlant here - It may be the MDO plywood, I think its a synthic composite or something thats designed for decks and extieror walls - some that im seeing have 10 year life.
Is this what you were suggesting ?
Formply is like any plywood except that is has finish faces both sides and is probably more waterproof than normal plywood. Looking at Neal's beds, normal plywood would be fine so long as it's painted well.


For stands I will use Cinder Blocks @ 1.48 each they seem to be be the cheapest solution. As you stated.
I'm not sure what a cinder block looks like. (I just googled and it seems that they are like our cement blocks except that ours don't have coal ash in them).


The Valve you linked in the pic - Does that go center of bed or is it prefferable to be opposite the water input ?
It's not a valve but rather a fitting to allow you to connect fittings through a bulkhead (wall) hence the name. You can locate it wherever it suits you depending on what type of bed you're developing. If you were setting up continuous flow beds or raft tanks, it would be best to put the outlet at the opposite end to the inflow pipework. If you were doing flood & Drain, it doesn't much matter.


Again thanks for the information and suggestions.
My pleasure


PS - I am somewhat close to my bed design, I will draft enginnering drawings in Microstation or Autocad /scan completed plans and post - after I've run threw an attempted construction. Will include pricing for all materials and cut lists. With step by step instructions. If your interested
We always appreciate drawings, images and the like......they're a help to people who are just starting out.....to make useful decisions.

Gary

nwestwood
12th December 2009, 03:03 PM
With the Vinyl liner I could have put 1" foam board on the bottom and sides (inside) to help cut down on heat transfer. I considered it but didn't do it. It would be worth considering. With my fish tank, without wrapping it with the bubble and foil, it would gain or lose an extra 4-5 degrees per day. Just insulating the fish tank made a huge difference. At Nelson and Pade's demonstration setup, they insulate all the exposed pipes as well and said it made a dramatic difference. Also, they did insulate their DWC tanks on all sides and the bottom.

LFCummins
13th December 2009, 08:58 AM
Like the idea of the Rigid insulation board, see it comes in 1". Was considering sandwiching it between 2 - 1/2" plywood. Wonder how it would do thermally as the bottom, all 4 sides, create a hinged top.

Neighbor loses everything each winter / and summer - Ambient temps are of major concern. If I can get a good 6-10 degrees then Ill be good adding frozen gallon jugs when its hot, tank heater in the winter. I juss might be able to go year round,

To promote growth in the winter 1" x 1" frame with black plastic, is set over beds at fall planting - allowing the plants to grow thru, while collecting heat and covering a large portion of the beds to prevent the loss. Course cover all the piping w/ the insulation from Lowes.

Any thoughts ?

nwestwood
13th December 2009, 03:24 PM
I would never get away with it in Utah. We were -5 (-18C) 3 nights in a row, and it didn't get above 15 for a week, but down in Texas, if your temps stay above 45 or so and you can keep the water warm, you may get away with it. In the winter, I let my greenhouse get down to 55 sometimes, but keep the water at 65+. The plant growth comes to a screeching halt, but they don't die. Generally I have to keep the air temps above 65 or tomatoes don't set and everything is in slow mode.

I will be real curious to see how it goes.