Aquarium - "full" ecosystem?

Question

Starting from this question I have another one. I was not able to find an answer, although it might exist.

Is it possible to populate a fish aquarium in such way that it requires "zero" maintenance?

• which fish?
• which "food"? (worms, shrimps...)
• which plants?
• which hardware?

What do I mean by that:

• all the food grows there (worms, shrimps, plants) in enough quantity for food and for population maintenance;
• the fish have full life-cycles (get born, live, die in-there); at least some of the fish;
• can make it with as few devices as possible: heaters, air pumps, filters, feeders, lights...; my best guess is that at least a mechanical water filter is necessary;
• should be free of pests (or: pests will be naturally removed by the ecosystem - snails, algae, food colonies...);
• should be "as small as possible";
• should look acceptably good;
• should "decently" survive electric power failures without battery-backed or combustion-engine backed power supplies; what would be the longest time expected before irreparable damage happens to the ecosystem?

I have managed something "close" with my bowl:

• no air pump;
• no artificial light (no live plants either);
• long lived healthy fish;
• only mechanical filtration with some bubble making (I allowed the filtered water to fall on the surface of the aquarium water from small height);
• filtering medium washed 2-3 times per year;
• some dry food added daily;
• some water added to compensate for evaporation;

I am aware that some of the conditions seem conflicting, but I am curios to learn from your experience what is the best I could get (IF I would start this endeavor).

Of course, a considerably large pond connected to flowing fresh water will be the best, but that is out of the question.

Answer 1

This question of yours is too large for one single answer.

I cannot answer what type of plants and animals are the best for your setup - it depends on how easy or complicated you want it to be.

But yes, it is possible to make a fully self-sustaining closed ecosystem; if you search for closed ecosystem or ecosystem in a bottle on the Internet, you will get several hits - like this one (source: instructables.com).

You need to make this type of setup in the largest glass bottle/container you can lay your hands on, and you need to be able to seal it so nothing goes in or out after you have closed it.

Here is a link to a relevant article on wikiHow with more information.

You need to use aquarium water and a clean container, and you will have to be sure the level of nutrients is at a level the plants and animals can handle and this is a lot harder than you might think (the nutrient level needs to be low to maintain a healthy system to avoid excess waste products).

One type of plant you will want in your setup is plants in the Elodea genus they grow fast and produces lots of oxygen by removing CO₂ from the water. The level of CO₂ will limit the growth, so it will be self-controlling to some degree.

You will need to read a lot before you start this project if you want to be successful.