Backyard Aquaponics
A place to discuss aquaponics

Today, I set up five 300mm satellite pots in which to put my first plants.

My latest round of test readings suggest that everything is on the rise, so setting up the satellite pots is timely.

We've got our tank near the shed door at this stage so I've just mounted the pots on top of the fish tank. As we expand the system, I'll make a more permanent arrangement.

I filled the satellite pots with clay aggregate out of my bio-filters so I'm hoping that the pots will serve as mini grow beds.

I upgraded to a larger pump.....from my 1000lph Chinese aquarium pump (which you couldn't kill with a stick) to a Rio 4500lph aquarium pump.

Each of the plants will have its own water supply - they are all hooked up to a single outlet. I'm opting for continuous flow watering at this stage.

Each of the satellite pots is lined with a "pot sox" to stop the clay aggregate from washing into the tank.

While they are relatively expensive to set up (about $25.00 each including clay balls), the satellite pots offer some significant benefits over other grow bed systems. You can remove individual plants from the system if they require a flowering nutrient regime or if they are sick. The pots are generally cleaned out at annual intervals so they won't clog up and roots won't be an issue.

I've set up duckweed tank just outside the shed door. It's about a square metre in area so I'm hoping to be able to get reasonable production happening once I get the parameters right. The previous experiment failed to produce anything startling.

GD, What are you going to plant in the pots?

Gary, I am in love with your megabin.

John, I'll probably begin with something uncomplicated like silver beet - it will cruise along quietly as we wait for the nitrates to kick in properly. I'll also plant some soft herbs like parsley and coriander. Once the nitrates are readily available, I'll expand the range of plants.

One of the really good things about the satellite system is that, because the system comprises pots within pots, you can move plants around easily. Fruiting plants, like tomatoes, capsicums and eggplant, can be part of our aquaponic system while they are in their vegetative growth stage and then be moved into a cluster of plants which are fed a high potassium/phosphorus nutrient mix for their flowering/fruiting phase.

The satellite system is also good for the fact that it very light. In fact, you can set it up so that the pots are almost filled with perlite and just covered with a layer of clay aggregate (or gravel) to stop the perlite from blowing around. At AUD$28 per 100 litre bag, perlite is a good growing medium. Of course, you can also use coco-peat - another good growing medium.

Dave, I like the mega bins, too. While we still have to determine how effectively they will grow fish out to eating size they are certainly a good tank for growing fingerlings. We will probably use mega bins inside (in a controlled environment) to start fingerlings off at the start of winter and then finish the fish off outside in a larger tank as the weather improves - for year round production.

Excellent plan Gary, thanks.

I planted out the five satellite pots with silver beet, coriander, mignonette lettuce and bok choi.

I chucked a handful of duckweed (the long-rooted variety) into my system - a big mistake - I spent the rest of the day picking it out of my pump strainer.

Hi Steve,

What's your take on the water tests in the photo below. They've been static around these readings for weeks.

I haven't done any water replacement for about three weeks. I've topped up a total of 150 litres of rainwater in that time.....to replace evaporation and water used during sucking uneaten food off the bottom of the tank.

The pH remains static even though I'm using rainwater (slightly acid) probably because my two small bio-filters are full of oyster shells.

I've been feeding enough that I've been vacuuming the surplus off the floor of the tank about once a week.

The plants that I'm growing are spindly due to the lack of light (we open the shed door every morning and close it every night) - they only received direct sun until lunchtime.

I haven't had any fish deaths since the first week.....when five died on arrival and one somersalted out of the tank.

I'm curious about why I haven't started to see much higher nitrate levels.

I'd appreciate your assessment of what's happening in general.

Nice one GD... Did you weld up that steel frame yourself? That looks like one of the square plastic ponds that I was looking at, at the B store.

Joel if its the one I was lookin at at my local B store I ran away when I saw the price... I didnt have me glasses on( the pope always said "stop it or u will go blind") but the price tag looked like it said $85 lmao

GD, not all the nitrite is being converted to nitrate, hence your 0.5 PPM reading on the nitrite test.

Also, nitrate level is directly proportional to the IN from the food, and the OUT from the plants.

Wait until your nitrogen cycle is complete (zero ammonmia and nitrite) then you can asses feed/fish to plant ratio.

If your nitrates stay static, then your nitrogen input and the nitrogen taken by plants are in equilibrium.

If you want to boost you nitrates to say 40 PPM, then feed more heavily and then back off to the original amount when the levels have risen.

BUT DO THIS AFTER YOUR NITRITES COME DOWN TO ZERO.

Steve

Yeah well, thats not that bad really BK, my local pond shop is selling the same thing for $115

Joel,

The tank is a Viscount Mega Bin. They hold 780 litres and cost $275 (GST incl.).

While they are more expensive than an IBC, they are much more convenient to use. They are designed for the fruit industry but I find the height (about 780mm) perfect for use as a fish tank. At about 4' square they are very easy to accommodate in small spaces.

By the time I hook a couple of gravel growbeds up to the tank, we'll have a nice little nursery system. My long term goal is to start our fish off in this unit and then to move them to a larger system.....thereby extending the number of fish we can produce in a growing season.

The steel frame is an old gate we had lying around.

Hi,

My participation in the forum has been sporadic of late......largely due to work commitments.

I've done little with my system in recent weeks other than experiment with a sedimentation tank (to capture fish waste). The results were fairly ordinary so I've since decommissioned it.

The focus in coming weeks is to relocate the tank to the other end of the shed and to establish a more effective growing system. I've erected a steel framework......3 metres long by 1.25 metres wide and about 2.2 metres high.....on which I want to expand our growing capacity.

Gravel beds are a known quantity......in terms of their advantages and disadvantages......and I'll eventually put one or two together. In the meantime, I'm focussing on learning more about alternative growing systems and media.....particularly coco peat.

I've been lucky....I still have 43 of my original 50 Jade Perch.

It's a busy time of year for a lot of us, look forward to your growing medium results. Your new framework will hold various medium grow beds then?

Hi John,

The framework will hold a variety of growing systems......satellite pots, trays, tubs and a small Deep Water Culture system......and a variety of media including coco peat, gravel over clay balls (to reduce weight while providing more effective plant anchoring than clay balls) and possibly even some perlite/vermiculite.

I also want to experiment with a type of bio-filter called a fluidised bed bio-reactor.......a fancy name for a 2 metre (6'6") section of 150mm+ (6"+) diameter PVC pipe, some fittings and some grit-blasting silica.

Arguably, the most obnoxious issue confronting aquaponicists is the fish waste that builds up in small bore pipework and grow beds so being able to convert (rather than remove) the waste is also a priority.

I hope to achieve this with a trickling bio-filter comprising a drum filled with shade cloth and a handful of compost worms. The theory is that the fish wastes will be trapped on the shadecloth where it will be exposed to the bacteria upon which the worms will feed. The idea is to retain the full spectrum of plant nutrients while ridding myself of the blockages and mess that accompanies the fish waste.

My goal is to come up with a compact and lightweight (relatively speaking) aquaponic unit which will produce consistent results.

I'll be assembling some of the system in the next couple of days...then I'll post some photos.