How to change fish tank water effectively and safely?

To change fish tank water effectively and safely, follow these steps:

1. Turn off all electrical equipment in the tank.
2. Use a siphon to remove about 25-30 of the water from the tank.
3. Use a water conditioner to treat the new water before adding it to the tank.
4. Gently pour the treated water back into the tank to avoid disturbing the fish or decorations.
5. Monitor the water parameters to ensure the tank's environment remains stable.

By following these steps, you can change the fish tank water effectively and safely for your aquatic pets.