Backyard Aquaponics
A place to discuss aquaponics

must be doing something right? there are weeds growing in the GB's!

after the liner goes in, and this thing starts cranking up, I will be thinking about an upgrade.

Trying to decide between a few options:-
1. vertical Zip type grow towers.
2. put some decking over the pool and have say 12 x 6m NFT channels. plus extra bio-filter?
3. stronger decking and more grow beds over the pool.

For option 1. I reckon 20 towers around the south side of the pool big expense getting the towers but the structural support would be fairly simple.

2 and 3 cheaper cost out lay for GB's but more expense for the decking, but I would gain about 25m² of usable area.

How many of you have green houses? are they needed in Perth?

Maybe in Perth it would more important to have some sort of shading to keep the sum off?

I think you would get the most benefit from grow beds. Both Towers and NFT will give more more issues with temperature swings and are both limited to fairly small plants. The Zipgrow towers do have the benefit of being filtration but are difficult for some people to plant (you need a planting bench to secure them down to while you pull the media in/out of them.
NFT Tubes, I have never been very impressed with the results compared to what I can get with the other methods. Only ever did very well for me for Basil through the summer and the growth of lettuce in them didn't impress me compared to how lettuce has done in the Zip Towers or Rafts. Everything else I have done has done better in Media beds. For Personal backyard growing, you can't beat the media beds for flexibility/productivity/ease of use. They may cost more (structure) to set up but since they provide you with plenty of filtration they are lower maintenance than the other methods and you can grow just about anything in them if you so desire.

Hard to beat grow beds... for ease of use...

Not sure I'd agree with TCL about NFT results.... but that's probably more to do with the fact that most people are using round PVC tubes... for what they call NFT...

NFT isn't limited to "small plants"... any more than DWC rafts are...

So Rupe, where would you choose to grow say, tomatoes? NFT or media beds? Even proper NFT troughs could clog with roots of large plants and I have only seen a rare few backyard set ups using the proper troughs, most are doing holes in large PVC pipes. And I must say I've not seen much in the way of tomatoes being grown commercially in NFT, most of the commercial hydro toms I've seen seem to be in rock wool slabs getting drip irrigation or sitting in a shallow trough or sometimes in buckets of media (so that would be Media or Modified NFT in my book.)

I will admit it really is possible that my results are largely due to some likely imbalances in nutrient levels in my systems, my experience seems to indicate that when using the same water for NFT, Media beds and DWC, most of my plants seem to fair better in the Media beds. Now if one is able to get perfect nutrient balances perhaps there wouldn't be much difference in productivity but seems to me that rarely is a backyard a "perfect world" and the plants in the media beds seem to do better even when the chemistry and nutrient levels may not be so perfect.

sounds like horses for courses,

The towers appealed to me as the provide a large BSA with a small footprint, but would be more suitable for lettuce, basil, chard etc. Tomatoes and cucumber support in a "tower" would be a problem.

In regards to the NFT I saw these they are oval shaped, is this ok or would the square ones be better?

The towers do have a great amount of BSA and you can grow the vines in them, only issue is you loose the portability so you have to make sure you can easily access them and the trellis you build around them.

I'll let Rupe answer about those NFT tubes (I can only guess that the flat bottom ones are better.)

Yes TC, but I would probably just use towers for lettuce and basil etc.

on those oval NFT channels, I thought they would need cups for the plants.

Looks like the plants have ben just dropped in?

Picked up the LDPE liner today,

now to see how many mates are available for the install?

Should be a fun day

the only unknown is the edging for the liner?
was thinking of something like a poly garden edging.

got to be something that can be nail gunned to concrete.

I was planning on hiring a ramset nail gun.

Well I know around here you can buy 1/4" by 1 1/2" PVC strips that are fairly flexible (it is what I used to screw the insulation up in our addition instead of having a bunch of big ugly washers on the screw heads.)

Anyway, you can get tapcon screws that can go into concrete and then use whatever edging or trim type material to secure the liner (might even want to roll the liner around the trim material.)

I was thinking of this stuff. Would like to fold over the edge but not sure how flexible the liner will be?

Expect the liner to be fairly flexible in at least one direction at a time but if you are trying to roll it around some edging and bend the edging at the same time it might be tricky. I don't think I would try to bend the edging around the liner, you actually want to roll the liner around the edging if you can and use the edging like a batton rather than trying to fold it around as a clamp (since I doubt the garden edging will fold tight or do much to hold or clamp the liner in any way.

I did mean to say fold the liner over the edging strip.

good to hear.

after getting a nail gun demo from Hilti I am loosing faith in my plan to nail the liner into the pool. Also it would still leave me with several issues such as lack of GB space, high pumping losses, Steps to negotiate, slippery liner to walk on.

So I was thinking of an alternate plan: this would involve filling the pool with sand leaving a sunken FT on one end and it's liner over the whole pool area. the pool are other than the FT would have 200 - 250 gravel to form a large GB. the liner under the GB would slope to the FT with subsoil drainage pipes to aide water return.

The subsoil drains would have a tee on the end with the upper edge being a stand pipe and a small drain in the underside to drain the GB for a flood and drain system.

Do you think this is feasible?

Otherwise I'm looking at filling the pool, paving the top and buying lots of FT and GB at the end of the day a better system but a bit out of my budget at the moment.