Aquaponics

Where fish feed plants and plants clean water. The whole reason this site exists.

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Aquaponics is a closed loop: fish waste feeds plants, plants clean the water, the loop runs indefinitely if the inputs (fish food, water, electricity) keep flowing. It's slower to set up than hydroponics and harder than aquariums, but a working system runs with very little intervention.

1. Decide where the tank lives, then where the plants live

These are separate decisions and they matter more than the species choices. A fish tank in an insulated basement holds 14-20°C year-round; the same tank in an unheated greenhouse swings from 5°C to 35°C. The grow beds can be in a different envelope from the tank: tank in basement, beds upstairs in a sunroom is a real configuration.

The aquaponics system designer lets you set both locations and tells you what fish and plants are viable. Tank in zone 5 underground without heating won't support tilapia; outdoor pond in zone 9 unheated won't support trout. The designer surfaces these conflicts up front instead of after you've stocked.

2. Pick fish that match the tank temperature

The food-grade fish catalog has 61 species filtered for aquaculture use, with regional legality data, climate zones, and outdoor pond viability. Tilapia is the most common starter fish (tolerant, fast-growing, easy to feed) but is prohibited in cooler-climate jurisdictions because of escape risk. Trout are the cold-water equivalent. The catalog flags both clearly.

3. Plan the beds

Real systems often have multiple bed types sharing one loop: a media bed for fruiting crops, a raft for leafy greens, sometimes a vertical tower for herbs. The designer lets you add each bed section separately and assign crops to specific beds. The grow-bed media reference covers what to fill the beds with , LECA and lava rock are the standard choices, limestone gravel is the most common mistake.

4. Match plants to beds

Each crop in the edible plant catalog lists which growing systems it works in. Tomatoes in NFT won't work; lettuce in a media bed is fine but inefficient. The designer's bed assignment check flags incompatible combinations.

5. Cycle the system before adding fish

Same nitrogen-cycle process as a fish tank, but the bacterial colonies grow in your media bed too. Plan 4-8 weeks. The system isn't ready for fish until ammonia and nitrite read zero and nitrate is climbing. Don't add fish based on a calendar , add them based on water tests.

6. Size the physical system

The system sizing calculator takes your fish tank volume and derives grow bed area, pump flow, sump volume, and daily feed amount using the UVI ratios that are still the standard for hobby and small-commercial aquaponics. If you've already used the designer, the sizing tool reads your design and pre-fills the inputs.

7. Supplement honestly

Aquaponics chronically runs short on potassium, calcium, and iron because fish food doesn't supply enough of any of them. The designer's supplement section gives you weekly dosing amounts for potassium hydroxide, calcium hydroxide, and chelated iron , in fish-safe forms, not the sulfate-based products hydroponic growers use. Dose by leaf symptoms, not on a schedule.

8. Cost reality check

The running cost calculator covers pump and heater electricity. Outdoor systems in mild climates cost $5-15/month. Indoor heated systems cost $50-150/month. Aquaponics is cheaper than hydroponics ongoing because you skip the nutrient bill, but the setup cost is higher.

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