1. Reason: Guppies may shrink their tails and fins because the water temperature changes too much, and they are sensitive to external changes. If the water temperature in which they live suddenly changes greatly, they will be stimulated, causing them to shrink their tails and fins.

2. Solution: If breeders want a simple way to treat guppy fin shrinkage, they can keep the water temperature at about 26 ℃ first, and then use a heating rod to keep the water temperature in this range. After they adapt to this temperature, the tail shrinkage and fin shrinkage will be alleviated.

1. Reason: Guppies' tail shrinkage and fin shrinkage may also be caused by poor water quality. Although they can live in poor water, it is easy to breed bacteria if the water quality is too poor, which leads to their tail shrinkage and fin shrinkage.

2. Solution: Breeders need to change water immediately to keep the water clean. Also open the filter and clean the filter material to prevent bacteria from affecting their bodies again.

1. Reason: The tail shrinkage and fin shrinkage of guppies may also be caused by bacterial infection. If there are bacteria in the fed food or they are not treated in time after trauma, they will have tail shrinkage and fin shrinkage.

2. Solution: The breeder needs to clean the sick fish with potassium permanganate solution first, and then disinfect the fish tank with potassium permanganate. This can avoid the growth of bacteria and reduce the probability of infection.