Backyard Aquaponics
A place to discuss aquaponics

I borrowed a camera today and took this snapshot of my little baby tower inher working glory... to date no water has dripped out of the system (yet)..

Nick - Good info. Will definitelly look at using towers to supplement grow-beds in my system and therefore allow higher stocking rates. I just hope that the material is safe and also that the heating process (used when making the planting locations) does not cause the structure of the material to change and therefore leach more chemicals (probably not a problem).

Murray - Good to hear your plants are doing okay. It is interesting that your Jades are eating only duckweed now. My silvers are not really interested in the stuff at all. I had thought that they were eating some at one stage, but I am not so sure now. One issue with duckweed as a diet may be gettign the required nutrients, minerals etc to the fish and the plants. This is an area I think we need to know more about (ie getting correct nutrientsand minerals to plants). After all, what is the point of growing a plant that has no nutritional value to us. In hydroponics the nutrient fed to the plants is full of all sorts of stuff (much of which I reckon probably makes the food unhealthy). Alll the same, nutrient balance is a major consideration in hydroponics and also needs to be for aquaponics.

Steve often talks about depleted soils meaning that veg is not much chop anymore. The same would apply to aquaponics. Just because a fish grows and shits - and then plants grow on the nitrogen, does not IMHO mean that the plants will be nutritionally complete. EG, I don't want to end up growing spinach for iron - but having the spinach devoid of iron.

I think a specific thread is in order. Will start one under plants.

Vb, its more the trace minerals, like copper, chromium, selenium and so on.

Any one keep chooks and feed them the ridley pellets? take a close look at the mineral analyisis. HEAPS of added minerals.

I suspect there is more than one way to skin this proverbial cat (clean this fish? )

VB / Steve, I have just switched to "Aquarium Science" High Protein Fish Pellets "Sinking" as a supplement to the Duck Weed. I am not so worried about there not being enough minerals etc in the Duck Weed at this stage, as I am of using up my DWeed supplies faster than it will grow.
I think it is a good point that the uptake of minerals can only happen if it is there in the first place
I am going to have to make two or three grow beds specifically for the production of DWeed. Jade Perch really love the stuff..
The Jade go for the sinking pellets much more readily than the other Native Pellets I have been using.
I am amazed at how clean and clear the water is now, since I have gone off those Native Pellets and switched to the DWeed the water is crystal clear.
Muzza.....

Muzz, good to hear from you! You've made my day re: the jadeperch liking the duckweed

Yes Steve, I can say they really go for it...... Long term, provided it has all the necessary minerals etc, and I guess that will depend on what one feeds the duck weed....I was hoping to feed them on the same system, but perhaps I should use Aquasol or something like that to feed the duckweed just to make sure it has all the "stuff" in there.
What do you think Steve / VB ?

Aquamad, your mini tower is looking good !
Muzza

Could do, muz.

you could use some of that mineral rock in the duckweed tubs, i assume its going to be seperate to the main system if you are going to use aquasol.
I'm going to try and beef up my worm production, i may powder some of that mineral rock i linked to and mix that into the worm farm.

Yes Steve, I will have a separate system for the duckweed I feel.....It does not like too much water movement anyway according to what I am reading on the Forum.
The mineral rock ? where do you get that from ?
Muzza

Muz, it was under the 'plants" section. Here it is again http://www.orchidimages.com.au/product.html

$7.50 for 1Kg. And i think that would be more than enough as its going to have water running over it it will release it minerals a lot quicker / easier than if it was incorporated into soil, as as AA stated you don't want to over do it. It looks like the place delivers, so may be worth while getting multiple bags to share with people in the same area. Any one in MELB interested?

RE the duckweed, my idea was to still have them connected to the system, but with a very slow, low entry point, waterflow in/out of the tubs. That way the nutes to the duckweed are maintained without disturbing. read: "less work"

Some of the 'polluted' water coming straight out of your fish tanks should be diverted through your duckweed tubs at the same time your grow beds are being fed.

Duckweed can cope with ammonium....particularly at the levels that are likely to found in the fish tanks.

If it's not killing your fish, it certainly won't kill duckweed.

I rummaed through my gardening supplies this arvo and was struck by inspiraton... so off to the B shop, got a few odds and ens, and came home to start on my next tower... below are the step by step images as I built the outlet pipes/assembly...

set 2, drill hole

next, insert tap adaptor...

another view, sormwater cap fliped over