Backyard Aquaponics
A place to discuss aquaponics

Hi Gordon

I am interested in seeing how you go with the Murray Cod. I understand that they tend to cannibalise each other if not kept at very high stocking densities?

i will be following with interest!

Nice harvest!

Gabe, I've just been talking to my Murray Cod supplier, and he says the cannabilism will happen with very low, medium, and high density! He sees it in tanks with 10 to 5000 Cod in them.

Hopefully I will have a couple of hundred 50mm fry by the end of the week.

These are now coming at about 1kg/day


After less than a week of me ceasing trout feeding, this deficiency came on very rapidly. Barely noticeable on my pics on the 16th, very obvious on the 21st after being away for a few days.



I think it is Iron deficiency, so I've added some blood and bone, as well as some Seasol, and peeponics has been in operation for 3 days, and will maybe continue another day or so, and the Murray Cod are due around the end of the week.
Some of the tomatoes are only showing a few slightly paler green leaves, but the strawberries look good. Asparagas looks normal too, one spear was about 30cm high yesterday morning, and this morning I thought I'd pick it. However, it had more than doubled in height and sent out all its branchy leafy bits!
There is another coming up today, I think I'll sneak in and grab it before it gets away from me!

Are those young or old leaves. If old not may not be iron deficiency.

I'd say middle aged- the very oldest lower leaves have no chlorosis at the moment, nor do the youngest leaves. The affected leaves are now starting to turn red around the edges and a few are starting to die off around the edge too.
Not all the broc seems to be affected though. Some of the chard leaves are a bit pale too, but other chards are unaffected. The silverbeet looks healthy as. Most of the broccoli is coming out soon anyway, I've got a whole lot of corn seedlings to plant and need some space.

Looks like you might be experiencing the sudden loss of nitrogen as well as warm weather being hard on things like the Kale. Looks like some aphids on the broccoli.
Interval chlorosis with the bronzing is often actually a sign of low potassium and plants suffering from a lack of potassium will also be more prone to pests and mold/mildews. But growing the plants out of their appropriate season can also leave them open to many of those same issues.

I haven't checked Nitrates lately, but will do so today. I have been adding heaps of K all through the growing season, but stopped adding KOH and Ca(OH)2 when I stopped trout feeding, as they are not required for pH balance.
However, I dont really understand how 2 plants can be showing this chlorosis so suddenly, yet another broccoli in the same GB, and in other GBs shows none at all. Even on the plants with it, it is only on a few mid sized leaves, most are not showing any hint of it.

Yes, lots of aphids in the broccoli, which I have been leaving untreated deliberately. I'm removing leaves, branches and whole broc and chard plants and feeding to the chooks and ducks each day, aphids for a bit extra protein. I'm making space for other plants, so all the brocolli will be gone by the end of this week, and corn, celery, chard, zucchini and melons are going in.

Today I'll be picking and preserving apricots, before doing another batch of tomatoes tomorrow.

Aphid farm for the chooks I love it! Classic example of the problem being the solution. You'll be encouraging predators too which will help out next season. I wS fiercer pulling out dandelion from my soil garden. Then I started eating it. Problem solved.

Ive never heard of using blood and bone as an additive, wouldnt this load the system with phosphorous

It worked well last time I used it Charlie, details a few pages back. It has more Potassium than Phosphorus.

9.9%N, 7.4%K, 3.7%P, no algal blooms or any other apparent effects.

I add a handful of blood and bone or chicken poop to my system when I see the leaves getting yellow. It works well for me. I read somewhere on the forum that it's not recommended for health reasons but I figure that people have been adding it to their veggie gardens for many years.

Thanks guys, Im assuming you go for an organic version by Yates or similar?




Edit: haha, you dont want to know what my spell check changed 'organic' to lol

I'm using Growth Agriculture's "Organic Based" liquid B&B. It didn't upset the trout, and I don't see a problem with using it now, when I have no fish in the system.

If your bio-filter is overloaded and you go adding things like blood and bone meal then it would be a bad thing but if you are in a fishless period............ It could probably be ok.

Seaweed extract is a good source of potassium if you are not adding the pH adjusting kinds and need some extra trace elements anyway.

I would probably avoid the chicken poo in my systems just because of the likely hood of introducing e. coli and/or salmonella into the system but I grow lettuce for sale so I'm very careful about avoiding system contamination. Chicken poo in a veggie garden generally should be composted before use too or allowed a certain amount of time before harvest of any plants eaten raw after it's use but for your own home personal use, it really is your own decision. I personally don't like the idea of chicken poop in my salads so I tend to err on the side of caution and compost all warm blooded animal manure before using it in my gardens.