Originally Posted by Beej1254
Although great advice it sounds like you are giving us recommendations for a planted aquarium and not an aquaponics system. Aquaponics systems rely on the fish waste to produce edible plants outside of the aquarium in a grow bed which is then pumped back into the aquarium to complete a cycle. This way the plants feed off of the nitrates and clean the water for the fish. All commercial aquaponics systems I've seen use large fish in large quantities to the point where you get extremely overstocked systems powering plant growth. But it seems wrong and a low quality of life for the fish. I'd imagine on a much smaller scale you could produce a decent bunch of smaller plants or even just one of a certain kind without overstocking a tank too much.
My issue with such a system in a 55gallon would be the decrease in KH
and increase in GH
On my salt water system I use a sump 3/4 the size of my display tank to grow macro algae to keep nitrates 5ppm or below. But I still do small weekly Water changes to restore the lost the lost calcium and other minerals. And this tank is far from overstocked.
For freshwater stocking levels or slightly overstocked I would say you would need a similar arrangement in addition to the plants in the display tank to make a large dent in nitrate levels. In all of the low maintenance tanks I have seen they have all been well below fully stocked.
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