Backyard Aquaponics
A place to discuss aquaponics

I was having a brainwave, and hoping to bounce the ideas off others.

I'm trying to figure out a way to make it as labour friendly as possible. I've looked at the UVI system, and it looks painful. They clean out the netting at certain times to control nitrite levels. Leave it longer to have lower nitrate levels, less often for higher levels. Or so my understanding of the theory is. It just sounds labour intensive and annoying to be continually cleaning out the netting.

How about a split up system. So fish in a big tank(s), the waste goes through either a large settling tank/rff, or a good drum filter. Whatever is most efficient. Then the waste is pumped direct from that into a large mineralisation tank, which is constantly bubbling and turning over the waste.

Next there is two or three seperate DWC systems. Each system (and the MT) has a arduino nitrate sensor in it, to keep the systems at a certain level. It'll take some tweaking, but say one system will be for fruiting plants, and they grow best at a higher nitrate level, so if the sensor senses the nitrates are below a certain optimum point, it'll pump the higher nitrate water automatically into the certain system to keep the levels at optimum amounts. And pump some of the excess water back into the fish part of the system.

The DWC beds can be powered with a simple low wattage pond pump, which in the scale of things won't cost very much.

The thing I'm not sure about, would the mineralisation tank handle the conversion of ammonia/nitrites/nitrates? Or would the water need to go through something like bio balls, to finish off the ammonia conversion?

Sorry if this seems vague, I'm just thinking out loud, and trying to figure out a system that's minimal on labour.

A mineralisation tank isnt really to provide a place for nitrification, it is to mineralise and reduce the wastes so nutrient rich water (not prodomately nitrates) can be extracted, skimmed and returned to the system. Nitrification and therefore nitrate colonisation will occur on every surface through the entire system, usually the greater percentage in the biofilter. Nitrate is a required fertiliser but is still only one very small piece of the pie as far as nutrients and minerals go. I have very limited understanding of nutrient profile requirements for plants and how commercial operations control them and I doubt any of the current operations would give out this information to the public. I would expect some very expensive sensor control for a range of parameters.

Yep.

I am not sure that a higher nitrate level is useful for fruiting plants as it tends to produce leafy growth, normally potassium levels up for fruiting.

I will be interested to see where this goes.

and phosphorus.

So you'd still need some sort of bio filters to do the nitrification. If I put it after some sort of drum filter, it'd cut down on the cleaning required I'd imagine. Then I could still pump the water from the MT tanks into the separate systems, and could experiment with potassium & phosphate levels in the separate systems.

I don't think the nitrate sensors would be that tricky.

I shall continue my pondering.

Snazzy
http://www.vernier.com/products/sensors/ion-selective-electrodes/no3-bta/

Quality
https://www.google.com.au/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&cad=rja&uact=8&ved=0CGoQFjAI&url=http%3A%2F%2Fwww.hach.com%2Fasset-get.download.jsa%3Fid%3D7639981839&ei=mciiU4OhAc7pkgW_mYGgCg&usg=AFQjCNGY-vP3Zk2DouGfrh-UKK-cXYrdAw&sig2=oCpKZKhyHg1EpuhmxtsWBA&bvm=bv.69411363,d.dGI

Cheap
http://www.amazon.com/NEULOG-Nitrate-Logger-Resolution-Maximum/dp/B00B76OW1O/ref=sr_1_1?ie=UTF8&qid=1403177276&sr=8-1&keywords=nitrate+sensor

The vernier was the one I was looking at. The electronic parts would be simple enough to setup.

I'll have to hunt for a phosphorous and potassium sensor though. I think they'll be harder to find. I might have to look into this:
https://www.kickstarter.com/projects/90 ... -sensor-fo

Thanks Charlie for posting those links, are all of them capable of being hooked up to dosing pumps? I'm trying to become more familiar with the technologies but I get lost in the product info

Colum, I use a colorimeter to test for phosphates, but it can also test for nitrogen (all forms), sulfate, iron, and numerous other micronutrients. For NO3 testing I use this meter http://www.agriculturesolutions.com/pro ... 743-detail

and I also use their same type meters for measuring calcium and potassium as well...

These are all very expensive methods, but worth it when you are either in a research or commercial production stage. They only allow me to test for ppm concentration though, rather than monitor levels and dose nutrients into the system. I'm wondering what are the advantages of using a NO3 probe as your leading factor in dosing your system rather than just using an EC probe to determine when the system needs to be injected with MT effluent? If you have a good hold on the standard composition of your MT effluent, then it should be fine to use an EC probe instead, then just adjust deficient nutrient concentrations (i.e. potassium, calcium, iron) using supplementation. Or you could add these supplements to your MT water and let the EC probe/dosing pump do the rest.

just spitballing here .......

Hi Colum, that is the way I am heading for my next upgrade. My main GB`s will be inline as normal with the fish tanks, digester and main sump. A second system with perhaps only one or two beds has its own sump that circulates to the beds and back to the sump. A small water feed from the main tank keeps this second system topped up with any overflow going back to the main system.

The flow of water from the main system is regulated to keep the nitrates low in the second system.

I think the UVI system was intended more for fish production, with the hydroponic component providing the necessary filtration to reduce water usage. I also think the orchard netting component is needed because of the high densities of fish in the system. I'd like to think a better way to control nitrate levels is to use a much lower stocking density.

Anyway, I'm in the beginning stages of my large scale system, and cleared out 11 trees in my back pasture a couple weeks ago to make room. In my original small system I used Matala filter media, which is way easier to clean than the orchard netting. I'm hoping to build a single tank system with a much lower stocking density similar in design to the UVI system, only using an RFF and Matala filter instead of clarifier and orchard netting, and with raised DWC beds.