First, draw a bottle of water from a pond or fish pond with a good ecological environment and pour it into a fish tank.

Second, use water strictly. Tap water should be exposed to the sun for several days, otherwise chlorine will kill plankton.

Third, change the water. When plankton is visible, release water carefully to avoid dumping plankton.

Four, if you want to make water full of nutrition, there are two schemes:

1. If the fish tank is large enough, a small ecosystem can be directly established, including sediments, plants, shrimps and crabs, fish, plankton and other small organisms.

& amp (= National Bureau of Standards) National Bureau of Standards