Install a filtration system
A filter will keep the water clean and it will remove many contaminants, such as feces. There are mechanical filters (which trap debris in traps that can be emptied) and chemical filters that absorb dirt. Some filters need to be placed under the rocks or gravel of the aquarium, while others are hung at the rear.
When you have installed the filter you must add the substrate. That is to say, you will have to add sand, rocks or gravel to the tank. In addition, before placing it you will have to rinse it with tap water to remove dust. Of course, your fish will also need decoration and plants. Choose decorations that provide hiding places for your fish but look natural, such as rock structures. As for plants, some of the most popular are Javanese herb, water wisteria, or Javanese fern.