Backyard Aquaponics
A place to discuss aquaponics

I was thinking about your sweet potato leaves TCL. We need an intake of Omega 6: Omega 3 at the rate of 2:1. Could just balance it out with something else....

I know there are links some were on this forum about growing your own spirulina. It can be done really low tech I understand.

The biggest challenge with developing ones own feed is probably the balancing and figuring out if you are providing all the trace nutrients and supplements needed while still meeting protein, energy and fat needs while still not polluting the water overly much.

There is an area in the forum for putting links and such Frank. Go ahead and put that nutrition site there. Could also make a thread for it in the recipes section too.

Think the link is somewhere in the "Spirulina" thread....

viewtopic.php?f=3&t=2831

And you'll find other references to it in threads such as "Homemade vs Commercial Feeds"....

Seek and ye shall find....

Neat! Thanks for the pointers Rupe!

I've seen a handful Copper Sulphate (yer, the blue crystal we grew in a beaker at high school) used to clean an Algae bloom in a farm dam in Australia.

Yes, algae blooms & little fishes don't mix. Been thinking multiple systems and multi-tank (in parallel) systems are the way to go. Each effectively being micro climates you can use to produce yield as inputs to each other. Close the whole system in more, just harvesting a few tanks for human/commercial use.

I'd think the copper would kill the fish too...... No good for AP.

I use algae bloom to feed my fish. But too much too fast would be a problem. Need to be able to see down at least a foot into the water or starting to get too thick.

Chelle

Algae blooms are appropriate for extensive systems so long as they are carefully monitored. Most people find that too much algae in Aquaponics is generally problematic but I would also not recommend copper. Shade is far safer for the fish.

Yep, if you're going to encourage algael blooms... either go to pond based aquaculture...

Or have a seperate tank based system for algael growth...

IMO, trying to maintain a tank based algael growth system will be extremely difficult... unless you can control water, heat and light... i.e... a totally controlled, in shed system...

In which case you might be better off growing in vertical bags...

Is it worth the effort... other than raising larvae to fry... probably not IMO...

Amused that when I read DanDMan's 'control', that I read it as 'get ride of', when DanDMan wanted to encourage it. Guess that show the experiences I've had with algae. Spoiled stock water and news stories about fish deaths in the Darling.

Agree with Rup, if you're going to have it, it need to be in a separate system. When you think about it, growing algae does defeat the aim of an Aquaponic system. Instead of the nutrients going to the grow beds, it's being tied up in algae in the water column. In a commercial system, that's completely undesirable. In a complex permaculture system, diversity is good. But as Rep says, because algae of so fiddly, it easy to through a system out of balance. The fine control needed to control algae and the dynamic self balancing nature of permaculture don't go together. So algae in permaculture is like algae in the wider environment. One of the first colonisers in a succession from a disrupted system to a complex stable one.

When I suggested using Copper Sulphate I was thinking about it in a pond/system rehabilitation scenario. You got a 'dead' pond with an algae bloom. You add the Copper Sulphate to kill the algae, pushing the nutrient back into the water column. Then cycle the water throw a newly establish or replanted grow bed system. It needs to be remembers that copper is a plant fertiliser and will be used over time. Once the water is cleaned both of excess nutrient and copper, the pond is ready for fish introduction.

Does that sound like a viable scenario?

I was drawn to this thread by the reference to the Omega 6 bad boy in the thread name. Have related stuff to add, but will start a new thread with a slightly different name.

Gnoll110

You have hit on what truly interests me. Aquaponics is the integration of fish and plants .... but can this be done more sustainably in terms of Permaculture concepts? Algae is a superb and easily sustainable food for tilapia. It is also high in Omega 3... extremely high.... another plus... something I do not want to lose from my fish system. The down-side in conventional AP set-ups is the way algae clogs up pipes etc. The answer would be to lose the pipes and pumps that clog so easily. Economically a big plus. But.... the water still needs needs to get to plants effectively. Raising the growbeds and filling them with compost instead of gravel ..... and then wicking the water up into the compost would achieve this... as Synaptoman was describing some time back..... an economical and sustainabe answer .... without all the usual fiddling around with pumps and pipe blockages. The challenges would be different.... DO for one... how to effect the best system for wicking ...... and would the plants be getting any benefit from the nutritious water or only the wetting of the water? I suspect dissolved nutrients would travel up too but not sure of this. The compost would offer lots anyway.

Not sure. I would be careful of using copper. Found here.... There is quite a bit about the dangers of copper if you google it. Build up seems to be the real problem. The plants doing your cleaning would have to be destroyed perhaps.

Here....Barley bales thrown into algae choked water will also cause a die off.

We grow our tilapia fry in cultured green water (algae) as well as feed a 50% protein diet high in vitamins C, D and E. The combo makes a world of a difference in early stage growth, and we also experience greatly reduced early mortalities. The fry are able to browse on the algae 24/7, so they have access to nutrients in between feedings. We used to use belt feeders (continuous small amounts of food provided 24/7) at this stage, but after doing some of my own experiments in the hatchery, we found that the greenwater and feeding 5 times daily gave the best results. The belt feeders are rarely used now.

A local tilapia grower I supply fish to is experimenting with greenwater, chara, duckweed and alfalfa meal. I'm anxiously awaiting the results of that.

Interesting. Do you think he could match your results? I have never heard of chara, but duckweed and alfalfa would be easy here. I am interested in moringa as part of the feed once I have more than I can personally use. My trees are still young. Moringa leaves are quite high in protein, and exceptionally nutritious. I do offer Mulberry regularly, which gets stripped. I know DDM spoke of the fry loving a pinch of egg yolk rubbed in with brewers yeast. That would bring the protein higher. For the older fish I have just bought a floating solar light which I spotted and want to try attract moths with.

What do you use to get the algae levels up? I use ordinary cow manure. Seems to work well and I have read that it also increases zooplankton for the fry.

Chelle

Had my ears to the ground on the copper front for the last few months.

Spurred to post today due to a gardening Q&A program on ABC radio this morning.

First some extra background. Digging around on the net, I found that it's free ionic (like that released by dissolving copper salts) copper that's the problem. Once metabolised by plants & animals it doesn't contribute to free load. It can't push the free load to toxic levels. So plants that metabolically 'mop up' free copper after treating a pond for algae would be safe for composting.

The radio program included a question about none/poor fruiting in citrus (Mandarin from memory). One action suggested was driving a copper nail into the truck, if copper deficiency was the issue. One caller said the same had worked with Lychee. Remembering the previous paragraph, the total copper surface area would be important. Too many nails and you could push copper release too high.

I also found two other interesting titbits on the net.

Found a Coy Crap fanciers site that commented that you could copper treat a Coy pond (fist in-situ) for algae if done carefully. The same site said other fish like trout were too sensitive.

Testing for copper also has a twist to it. Some test just measure the 'free' copper. Some test actually release and measure bonded copper too. The second type of test is useless for our purpose (and gives positives).

More grist for the mill.