Backyard Aquaponics
A place to discuss aquaponics

Alright, I've been browsing the forum for sometime now and asking a couple of questions, mainly via 'pm'. On suggestion from some of the other users I have attached pictures of my initial small setup, with a couple of queries. On top of that I am building a bigger (much) system over the weekend and need a couple of pointers.

The system attached is compiled of two 100l tanks holding goldfish, one 'sump' to join the two together - this holds my pumps as well as heaters to bring the water up to around 25 degrees C - and a 100l grow bed. My timer fills the grow bed every 14 minutes (used to be twenty but after a little advice from RupertofOZ moved it to a quicker cycle)

The second picture shows a leaf of a bean plant that I have, it points to malnutrition but I do not know what to add, nitrate levels are acceptable, I add chelated iron every so often, what else?

Lastly and probably more importantly, my big system, this will be built over the next weekend. I will be installing a 4300l tank in a 4m x 7m green house. My problem is I do not know what to use as grow beds, my problem being that if I use tool totes again, I will need 43 of them (correct me if I am wrong) and I do not have the space, I see many people use half barrels, I will do this as a last resort but I was thinking of doing something different, like long beds spanning the length of the greenhouse. Any Ideas?

be missing the second picture, spot the newbie

Hi Axle,

Great to see your system. Looks good. Have you considered large PVC pipes cut in half? They're expensive but you can cut them to the exact size of your greenhouse. I think there is a factory in Pretoria that makes a 500mm pipe like the attached out of re-cycled materials (called cable-quality) I'll try and find their details if you want. Good luck and I'll pop in and see you some time when I'm up there again.

That pipe looks perfect, if you can find the details I would really appreciate it, I will start scouting around tomorrow at any rate and hopefully sort something out. I also come down Knysna way around once a year, so will definately be interested in visiting yours and the 'BIG' system.

Nice to see your system up and running Axle.... and the photos

do you need a heater in SA , and for goldfish ? what is your Temp now

You usually don't need a heater in SA (especially for Goldfish) but as stated the heaters are in the middle tank which does not house fish but rather pumps water to the grow bed (aka sump), I read in a Hydroponic manual that plants seem to like a nutrient solution of around 24 to 26 degrees thus the extra heat. In winter in Johannesburg we do go down to around -3 on some mornings so it is also a good precaution for the fish.

Any help with the nutrient problem shown in the third pic anybody??

not entirely sure that it is a nutrient problem. have you checked for mites and insects?

Axle - is that amrking on a lot of leaves? It looks like a water/chemical marking. Used to get marks like that in the dirt garden, when liquid fertilizer was too concentrated.

The reason that I assumed it was nutrient deficiency is that it has started on the lower leaves, the newer shoots and leaves are perfect and growing well, but as the bottom leaves mature these spots appear and it is slowly but surely moving up the vine. The plant is growing like mad and produces beans over 30cm long, but for this problem. I have checked for mites and such and have not seen any, but will make a point to look again in good light over the weekend.

Axle,

The contact for the 500mm pipes for the growbeds is a company called PETZATAKIS AFRICA (PTY) LTD. I'm sure they have an outlet in Johannesburg. A 6m length will cost you about R350/m and cut in half will thus give you 12m of 250mm high growbeds.

Cheers

Can you believe that they are one of my clients... I didn't even consider calling them. Thanks for the help, was busy installing the tank on my large system this weekend and discovered that the liner given to me has a side outlet rather than a bottom outlet, seeing that I have all plumbing cast in - another delay...

Hummm .... I sense another system thread about to be started.... with lots of pictures I'm guessing

Ah yes, another large system is in the making, this is actually a pilot that I am doing for a medical orginisation that would like to attach aquaponic setups to their rural cancer trial centres to help out the surrounding communities. The pictures and such will be entered into a new topic shortly.