Aquaculture is farming on water.
Many of the same principles as farming on land apply, and there can also be synergy between land-based and water-based farming - for example, chickens and ducks will find forage at the edge of the pond.
Permaculture is stresses the interactions between different organisms, therefore the most productive areas on a permaculture farm are the edges where two different environments come together. It is best to maximize the edge length of the pond; a square pond is a bad idea; one with crinkly edges is much better.
Because fish are cold-blooded, and because water provides buoyancy so they do not have to expend energy to hold themselves up all the time, they are much more energy-efficient organisms than land based animals. Feed:yield ratios of 1:1.15 have been reported for fish farms, whereas farming terretrial livestock achieves a 1:3 yield at best.
Nutrients dissolved in water are more readily absorbed by plants' roots. (This is the reason hydroponics works so well.) You can, for example, get 12-15kg of food per year from a single taro plant.
For these reasons, aquaculture is 4-20 times more efficient than land-based agriculture in terms of the energy used to make a unit of food and the yield per unit of area.
Water quality can be controlled to a certain extent by landscape design. Large stones placed in a pond will serve as a thermal mass, making the water cooler in hot weather and warmer in cool weather. Growing reeds helps to oxygenate the water. Freshwater reeds grow much faster than any land-based plants can, so make a good source of feed for herbivorous animals. Algae often form the bottom of the food chain in an aquaculture system and go on to be converted into larger edible organisms. Therefore, an area of still water with tree stumps where algae will grow can be advantageous.This category currently contains no pages or media.