How many grow beds can I fit in my greenhouse?

[Flemming Funch]

I'm putting up a 9 m2 greenhouse (374cm long x 249cm wide x 260cm high = 148" x 98" x 102" ~ 97 sq ft)

I'm having a bit of trouble visualizing how much I can put into it. I have 2 1000L IBCs, which I plan to use as fish tanks, and essentially do two separate systems. In part in order to have different fish in each. Tilapia in one and African Catfish in the other.

So, I know I'll need at least 1000L of grow bed for each system, and that I could very well have more. If I have 30cm deep grow beds, we're talking about at least 6 m2 of grow bed. For example, 2 beds, each 3 x 1m.

I'm planning to partially bury the fish tanks, so that I can use some of the space above them for grow beds. I will bury sump tanks completely. 

Since I haven't yet found the perfect containers for grow beds, I don't yet know what to do. I might construct them of wood with liner, or I might cut up some rainwater storage containers. 

I can see that if I put a 3 x 1m grow bed in each side, there's hardly enough space to move in-between. So, I'm thinking I'll have several layers. Like, oh, an 80 cm wide bed below, and a 40 cm wide above it.

But I don't know if I'm stuffing too much stuff in there and it won't work at all when full of plants. Or, if I do the same in both sides, the south pointing side will shadow for the northern side. So I'd love a little feedback on whether this sounds reasonable or much too cluttered.

I'm also wavering a bit on whether it is smart to have two systems, or whether I should just connect the water in the tanks and make it one system.

[Flemming Funch]

Let me answer myself, then, based on input I've gotten in other places, and looking a bit more at what others have done.

Probably a bad idea to try to squeeze that much into that small a space. Probably better to leave some space and keep it simple. 

So, I think I'm going for a more simple CHOP system. One 1000L IBC, 1200L grow beds (7 x 180L) and 500L buried sump (2 x 250L containers). I've located some suitable plastic containers from a local grow shop. So, a layout something like the attached, after playing around a bit in Google Sketchup.

[Wil Miles]

nah man go ahead stack beds on top of beds make it work it will grow as long as all plants get light ive had a 4 tier 6 ft high gow bed lol it was a solid flow, ebb and flow style ,but it worked. just remember the roots are the important part they need alot of space most plants need 12 inch deep beds check out youtube under diy aquaponics youll see something similar good luck

[Flemming Funch]

4 tiers, wow!

I can certainly see that I need to leave things relatively open for tinkering. I.e. not hammer everything permanently together right away, but be ready to move pieces around and expand along the way, as I start knowing what I'm doing.

[TCLynx]

be careful about burrying the sump completely,  You want to make sure that ground water can't get into your system and you need to have access to the sump to clean or replace or maintain the pump.  NEVER make anything in your system completely in-accessible or you will certainly need to rip everything out to get at that particular part.

I would recommend going a bit simple on the first system.  I always recommend against wood and liner grow beds now though as I've done it and regretted it.  Half IBC's make great grow beds in my mind.  Or 100 gallon Rubbermaid stock tanks if you need them a bit narrower but still want the volume for filtration.

For use of upper space you might look into using NFT or perhaps some Zipgrow towers.  NFT would require that the water be well filtered before being pumped to them but the Zipgrow towers don't require pre-filtering before getting the fish water.

[Flemming Funch]

I have been looking high and low for some of those Rubbermaid tanks I see people using, but they don't seem to be available in my country, France. I had started to think about cutting up closed rainwater containers. But a reasonable compromise is those containers I just found. 180L or 250L. That's a little small, so I'll have to duplicate more auto-siphons, etc, but that'll work. They seem to be easier to find space for than cut-up IBCs.

My current choice for sump tanks are 50cm tall 250L containers that are all open in the top, but come with a tight fitting lid. So I'd at the most put them so that the lid is at floor height, so I can get to them, but so I can put insulation around them in the underground part. I'll connect the two together with a pipe underground, and yes I've better be prepared that things can go wrong with pumps, etc.

Very good idea to think along the lines of NFT or vertical growing for what I can put above the initial media beds. In part because they make more sense after already having filtered solids through the media beds. In part because they're light, so I can probably add them later, without having to have thought through the whole construction plan from the beginning.