Aquaponic Gardening

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I started messing around with tilapia 2006-2010

2010 - the end of july i had to take  my system down

i am currently trying to get a piece of property to set up a scaled system.

basickly i dont have a system that is running

but i want to share my last 4 years with aquaponics

with members.......


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I made a mistake...this is my actual nitrite readings on the graph

Hi Francois,

Good going so far! How's the duckweed growing?

Hi All
Still no media but today I filled plastic baskets with small stones….-+6-10mm.
These baskets I used with my pilot project I have 8 off them…had eight grow trays with my pilot project and I used these to catch solids where my water flowed from the dam into my trays.
In these I want to plant sweet corn and beans in vermin castings directly into the stones and see how they do.
The duckweed in my trays seem to be doing well and the fish are happy…eating.
I have been feeding the fish worms only…my nitrite last reading on Tuesday was 4.0mg/l
I have not checked since…run out of testing tablets…. Test kits are very expensive here
With my pilot project over the last two years I really only checked ph alkalinity hardness
The rest I left to the fish to give me a answer…..eating fish are happy fish
Yust me thinking

Hi all

This is a load of vermicastings i made over the last +- 11 months.


5 meters long



hundreds of small worms



This load was made using paper, cardboard , a small tree I shredded, and vegetables scraps from a veggies shop down the road every other week.

These castings I now want to remove most of the worms and then use the castings for another veggies project I am trying to get started.
Not much work and the results are good compost.

Great stuff

What's your favorite method for separating worms from castings?

Hi All
Yesterday 80 male tilapia fingerlings I ordered……was delivered. (Hatchery)
I think my timing was bad because since yesterday we have had terrible windy and cold conditions.
I don’t heat water and with these fingerlings arriving now was not a very good idea but…...
Yesterday I introduced them into the system with water temp. +-12 degrees…no choice I had to get them out of the bag they were delivered in.
Very Bad idea, after releasing them in my system and leaving the fish for a short while when I looked again there was +- half of the fingerlings laying on their sides on the bottom of my tank.
I used a net and poked lightly at some of the fish on their sides and saw that when I touch them they would come up straight and swim away. With seeing that they swim again if I help them along I started moving the water in a circular movement in this sq. tank using a paddle. This basically got all the fish moving and surprisingly this revived all of the fish that was on their sides a few minutes ago.
I did this for maybe 5 minutes and it worked. After watching them closely and whenever it looked like one was going down I would help him along. By last night they were all still alive.
Then this morning when I got outside I found 4 fish again on their sides. I tried the same as what I did yesterday and saw that they are still alive. 10 Degrees Celsius
Not wanting to lose these fish I thought well it now or never and I took a bucket and filled it with water from my geyser….and slowly adding to my tank. I raised my water temp with 70 litres of hot water from my geyser.
The Kio in the system were fine and I wanted to feed them. I fed the Kio and I saw that the tilapia are also eating and 60 min ago they were almost dead from the cold water.
Proves once again to me just how hardy tilapia is.
With my pilot Project I used wild tilapia from a dam and never had these problems. They survived these gold conditions. My pilot project records lowest temp. 8 Degrees Celsius.
Hope I can get this lot to survive the cold.
We are starting spring now so our days should get warmer and that will be a great help.


Photo taken yesterday


 Photo's taken 20 min ago after all the drama this morning and they are all still alive.


Francois - your problem with the hatchery Mozambique tilapia is one I have also experienced and which troubles me.  As you correctly state, wild Mozambique tilapia are not nearly as feeble in terms of lower temperatures.  My trial unit ran on them and they fed all through winter.  Then I got some of the colour variations from a hatchery and apart from rather patchy growth, they are weaker than wild stock.  I saw trouble brewing with my open system and moved them into the polycarb greenhouse early this winter (Uitenhage is much colder than you guys).  In there, I did not observe them feeding all that much at temperatures below 14 degrees Celcius, which will be a disaster for your system as they will not feed most of the colder times of the year.


I will seriously consider some form of passive heating unit before winter to keep your system above 14 degrees Celcius otherwise you may just have to supplement nutrients or toss the tilapia for wild ones or koi. On a more long term view of the whole thing, I believe that from what I have heard from a number of people regarding the state of the hatchery stock, there is a need to improve the gene pool for use at lower temperatures.  It is crazy that the aquaculture version of a fish that thrives in the wild here does so poorly.

TCLynx said:

Great stuff

What's your favorite method for separating worms from castings?


Hi Tc
The castings I will put in small heaps on plastic in the sun and when all the worms have moved to the middle bottom of the heaps I scoop of the top castings of leaving the worm’s behind. After doing this you end up with most of the worms and castings separated. This takes time but it works ok.

Hi Kobus
To tell the truth I actually expected this ...these fish were grown to this size in temp. Controlled environment...not used to this cold. i was warned but i wanted to see for myself. This afternoon when i fed them they were braking the surface to get to the food so...lets wait and see.
I will have to live with what I have and make the most of the situation …summer is around the corner

Good Luck with the fish, hopefully the hardy ones survive and the ones you loose might improve the gene pool.

Hi all
Last night after dark I added 26 litre from my geyser for the cold night.
This pushed my temp to 25 deg.
Today this morning I left early still dark so I never checked the fish.
This afternoon when I got home I checked the temp.20 deg.
And....all the fish wanting food....all alive and hungry.
So over night and today I only lost. 5 deg.
And all still happy

Thanks Tc

Hi All
Very sad to say I lost 66 of the male tilapia fingerlings…
To say I really $#@%%^& up and hopefully learned a lesson for the feature
With this now I am reverting to Kio for now, the Kio handle the cold much better.
Kio fingerlings are very expensive if you compare them to tilapia, so I will stock over time.
1 Kio fingerling R15.00 and tilapia male R1.95 …… extra cost to stock my tank.
Yesterday my wife bought me 11 Kio, 4 +-100mm long and 7 +- 45mm long (R500.00)
Now I have 15 Kio and 14 Tilapia in my tank …..
I want to add more Kio as I go along.
I have been feeding the fish Kio pellets and worms.
I feed pellets in the morning and then worms 2/3 times a day.
The duckweed in the bottom grow trays are doing fine and the worms in my filter have settled in.
As for my system goes so far the system has been running no problems and I am very happy.
I still don’t have growing media in my grow trays…. I have not planted plants in the system as yet but I will have to do this in the next few days…. I am not really worried about the nitrates for now.
Water parameters I have not checked for at least +-2 weeks but I believe my filter bacteria is sorted and I have added a bag with shells in the system for the Ph.
Fish are eating so I am happy

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