Traffic light fish is suitable for living in weak acidic soft water. When rearing artificially, the PH value can be kept between 5.8 and 6.8. Water quality cannot be kept neutral or alkaline, otherwise they may have poor growth and development. At ordinary times, it is best to choose soft water for feeding, because hard water is easy to contain compounds or magnesium compounds, which not only has certain effects on their health, but also affects their body color. If the water quality in the breeder's area is hard, you can choose to boil it before using it, or you can choose to use distilled water directly.

In addition to water quality, attention should also be paid to the water used. Now most people use tap water, but tap water contains more chlorine, which has a certain impact on their health. Therefore, it is best for breeders to expose themselves to the sun for 2-3 days before use, so as to effectively remove chlorine from water.

It is most appropriate to keep the water temperature of traffic light fish between 22-26 ℃, because they belong to tropical fish and like higher water temperature. If the water temperature is too low, they will have loss of appetite and activity, which will affect their growth and development after a long time.

Although they are tropical fish, the water temperature should not be too high. If the water temperature is higher than 32 ℃, their resistance and immunity will decline, and they will also have irritable emotions.