Experimental Aquaponic & Hydroponics

Aquaponic History

In February 2013 I did a small experiment with Aquaponics, growing Basil above a home 20 litre fish tank. It was all done on a whim, without much research or understanding of the plants requirements. It was simple enough, a plastic box set on top of the tank with the filter pump (filter removed) pumping the water up into the tank and then allowing gravity to bring the water back to the fish. It was created after seeing these appear on a kick-starter project I believe.Home Aquaponics

I jumped at this awesome idea, and thus created this much simpler and far more home DIY version.Aquaponics Experiment 02/2013

So here I am nearly 2 years later, about to embark on a home hydroponics system. Did the aquaponics system work? NO! It pretty much failed. I had gone travelling for a good part of the year however, and left this little experiment to my girlfriend, but ultimately a few fish died & so did the basil 🙁

We were never 100% sure why, but made a few educated guesses. Firstly, basil is a sun loving plant and generally requires 6 to 8 hours of full sun per day. Home fish tanks are often kept for aesthetic reasons and so algae is considered the enemy. Algae however flourishes in the sunlight & so does your basil! That’s where it all began falling apart, if you want healthy basil you will have loads of algae and if you want to avoid the algae you cant have your tank in the sun and so your basil dies. An attempt was made to protect the fish tank & growing medium from sunlight, but it wasn’t extremely successful.

Sunlight ProtectionThe exposed gravel was becoming very dusty and as you can see above, the lid was added & the top was changed over to use net pots in an attempt to keep the environment clean.

The second reason was that I had never read up about the Krakty method of growth in hydroponic systems. The Krakty Method, simply put, leaves an air gap between the water level and the roots. This gap allows the plant to grow two different root types, air roots & nutrient roots, and as you can see in the photo above, I had not taken this gap into account. The water pump was turned off at night though, and so the plants had a dry period of around 8hrs a day when the water all poured back into the fish tank. That said the water pouring back into the tank was in its own a form of aeration (for the fish), so this might not have been a major player in the systems failure.

Krakty Air SpaceUltimately I think it failed on a nutrient level.

Stepping out and Exploring Hydroponics

So after much studies and many hours in front of Youtube Videos watching channels such as mhpgardener and KhangStarr010 I have decided to venture into this world, attempting to grow via the Krakty Method as mentioned above. I have my tank, a polystyrene lobster crate, I sourced net pots, rock wool & leca (clay ball growing medium) from hydroponic.co.za and so the adventure begins. Its ultimately going to be all about the nutrient mix, as I believe the polystyrene will be enough to keep sunlight away from the nutrient rich water (avoiding algae) and the entire design has been based on system I have seen & know works.

My biggest difference/experiment? Well I am going to attempt to be as organic as possible, it seems as though nutrient mixes that are commercially available are chemically designed to be of peak performance to the plant. Yes, that does sound like the perfect and simplest solution, but my desire to remain organic is driving my decisions. Its going to be a real test of balancing the NPK, all the trace elements, and pH.

I am still undecided as to where to keep the system, my current out door veggie patch has a constant onslaught of worms, caterpillars or bird attacks. I might just keep it indoors in a sun facing window simply to dodge pests.

Home Hydroponics

I am currently speaking to a local producer of sea bird guano in worcester, and he has put me in touch with another local hydroponic grower using guano in his system. Guano is generally high in nitrogen (N), phosphate (P), and potassium (K) which encourages plant growth, but I am most likely going to need to increase these NPK values. Magnesium Sulphate (epsom salts) must also still be added to create a balanced fertiliser. Epsom salts increases nutrient uptake and accelerates growth according to the Epsom Salts Garden Cheats. I am aiming for a pH level between 6.4 and 6.7 which I will test with a simple aquarium test kit.

So the Pak Choi has been planted in the Rockwool, and I will continue to give updates as the days go on. 🙂

Further Reading?

Hydroponics.co.za Quick Start Guide – https://hydroponic.co.za/hydroponics-quickstart/

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