About my system

Why I built it

We are a household that cares about what we eat, with a few health considerations in the mix, so good organic food matters to us. Our veggie patch was never getting the attention it needed, the food bill kept climbing, and decent fresh fish in Australia is both expensive and too often shipped in from places with questionable practices. Aquaponics solved several of those at once: fresh fish and a steady supply of organic veg from the back corner of the garden.

It also fits how I think generally. I run Frugal Energy building renewable power from reused batteries and panels, so a system built largely from salvaged and reused parts, and powered by my own solar and battery setup, was always going to be the goal.

How I started (and what I'd tell you to do)

My first attempt was a small bathtub build, before I had done any proper training. It got me hooked, but I was feeling my way in the dark on the things that actually matter: the nitrogen cycle, cycling the system, water chemistry and fish health. I no longer run that bathtub system, but it taught me the most important lesson on this whole site.

I then did Murray Hallam's aquaponics course, and it changed everything. So here is my honest advice: start small if you want, but do the training before you spend real money or put fish in. I learned that the hard way so you don't have to.

What I run now

My current system is based closely on Murray Hallam's Toteponics design, adapted to suit my site and the bits I had on hand. Right now it is all media beds. The bones of it:

• Fish tank, sump and media beds all built from reused 1000L IBC totes, with the media beds running blue metal gravel
• A settlement tank and a mineralisation tank, so I can turn fish waste sludge into a free liquid feed for the system
• Raised soil beds beside the aquaponics for root crops that do not suit media beds (these replaced an earlier wicking bed; more on that in garden tasks)
• Aeration to the fish tank and sump with a few airstones

A deep water culture (DWC) raft bed is on my list to add down the track, mainly for fast leafy greens like lettuce, but I haven't built it yet. When I do I'll write it up here.

Building it

Most of the build is reused IBC totes, besser blocks, salvaged timber and PVC from sourcing and Dural Irrigation. A few photos from putting the current system together:

Powered the frugal way

The whole system runs off my Frugal Energy setup: salvaged panels, an Epever MPPT charger, reused batteries and 24V DC straight to the pumps. No inverter, no mains in normal running. How I put that together is in the renewable energy section.

For peace of mind there's a backup pump on a separate backup system. A float switch detects when the main pump has stopped doing its job, and kicks in a basic bilge pump to keep water moving around the fish tank and sump. It is not running the full system, just enough to keep the fish alive until I get the main pump sorted. The best part for an off-grid build: the bilge pump is DC too, so even the failsafe runs off battery and solar, with no mains and no inverter in the way. More detail on the backup setup.

Water comes off my shed roof into 2 IBC containers, and I use that to top up the aquaponics system and to water my regular soil garden as well. No town water in normal running, so the system costs next to nothing to keep going.

The fish

I run jade perch, an Aussie native that's well suited to the Gold Coast climate, grows fast, is forgiving for beginners and eats well. More on where I get them and how I look after them.