Aquaponics
Consumables
The ongoing bits: food and pest control that won't poison your fish.
Fish food
The commercial food I use is Frenzy Fish Feeds Australian Made Premium Native Fish Food, a high-protein pellet made for natives like cod, perch and barra, which suits my jade perch. I buy it from eBay seller frenzyfishfeeds.
A couple of reasons I rate it: it's a floating pellet, so I can watch the fish actually take it and judge whether I'm overfeeding, and it's Australian made for native species rather than a generic tropical food.
Pellet size depends on the age and size of your fish. Start small for fingerlings and step up to larger pellets as they grow. When they're little you can crush the bigger pellets down (a coffee grinder works) until they're ready for full size.
One rule I stick to: only buy fish food with no land animal content in it. Your fish are freshwater natives, not livestock, and it keeps the whole system cleaner.
Making your own
To cut cost and waste even further, I make my own fish food. My rough recipe:
- Blended-up veggie scraps
- Cheap tinned sardines (a good cheap protein and a source of healthy oils)
- Some carbs (grains and the like)
Blend it all together, freeze it, then chop the frozen block into pieces to feed out as you need them. This is just what works for me, not a precise formulation, so it's worth a look online for a more refined recipe if you want to dial in the protein and nutrition properly.
Pest control
For pest control I use yellow sticky insect traps. You just hang them near the plants and they catch the flying pests: whitefly, fungus gnats, aphids, thrips and the like. 25X Yellow Sticky Insect Trap, eBay seller ibasetradingptyltd.
The reason I use these rather than a spray is the single most important rule in aquaponics pest control: whatever you use cannot get into the water. Most garden insecticides are lethal to fish in tiny amounts, and anything sprayed on leaves runs straight back into your system. Sticky traps are a physical control. Nothing enters the water, so there is zero risk to the fish or the bacteria. Frugal, simple, and safe for the whole system.
They won't stop everything. Crawling pests and caterpillars need exclusion netting or picking off by hand, but for flying insects they do the job, and they double as an early warning that something has moved in.