Some people do it for grass, some for fish, some for feng shui, and some are idle.
For me, none of this is.
On the contrary, I am creating a world.
What I raise is not fish, grass, snails, shrimps and mushrooms, but a system and a complete ecological world.
Look at the natural ecosystem. Do you need to change or filter? All you have to do is set up the system and keep all its links running normally.
Junior high school biology, producers decompose consumers. There are no fish, only aquatic plants, sunlight and microorganisms. The system works as usual, but if there is something wrong with the producer, the fish can't survive. Higher creatures look advanced, but in fact they are the most vulnerable.
It is also possible to suck fish droppings or filter for changing water, but if we restore the ecology of nature, nothing will work, and it will go on and on. Fish eat feces, snails eat fish feces and some microorganisms, feces and nitrifying bacteria convert these feces into nutrients, which are absorbed by aquatic plants, grow through photosynthesis, produce oxygen and are inhaled by fish.
All you have to do is feed the fish, then the water evaporates and then add water.