1 There are no obvious scars or diseases on the fish body surface, such as rotten fins, rotten bodies, bleeding, blindfolding, white spot disease, etc.
Fish eat normally, and it is also worth noting that they don't eat or eat less.
3 normal activity, no fin contraction, swinging from side to side in the same place, staying in one place for a long time.
The guppy is a kind of fish in the upper waters. If it is often downstream, there may be problems.
There is no obvious blackening on the body, which is mostly caused by poor water quality, which will seriously affect the life of fish.