Source: Building a Stylish Home Aquaponics System: The Basics – The Smart House
How I transformed my freshwater aquarium into an aquaponics garden for year-round organic produce (and stopped doing water changes).
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In this article we aren’t going to focus on my aquariums themselves, but instead we’re going to focus on all that waste the freshwater fish produce. … Where a hydroponics system requires you to add nutrients to the water to feed your plants (basically fertilizer), an aquaponics system uses all the nitrates produced by your fish as natural fertilizer!
it’s not quite as straightforward as sticking a plant in some nutrient-rich water and letting it grow. The water has to be in a near-constant state of movement for starters, and believe it or not the roots actually need to be exposed to the air as well (otherwise you get root-rot and your plants die). … The answer is to use a very clever plumbing contraption known as a Bell Siphon which is designed to do exactly what we need in our grow beds.