Here's why:
* Disease: Dead fish can indicate a serious problem with the water quality in the tank. This can include high ammonia levels, bacterial infections, or parasites. Buying fish from such a tank puts your existing fish at risk of contracting these problems.
* Stress: The surviving fish in the tank are likely stressed by the presence of dead fish. This stress can weaken their immune systems, making them more susceptible to disease.
* Poor Care: A store that allows dead fish to remain in their tanks likely doesn't have the best practices for fish care. This could mean they aren't changing the water frequently enough, aren't properly monitoring water parameters, or are overcrowding the tank.
What to do instead:
* Find a reputable store: Look for a store that has clean tanks, healthy fish, and knowledgeable staff.
* Ask questions: Don't be afraid to ask about the fish's health, the store's water quality protocols, and how they quarantine new arrivals.
* Consider a different store: If a store has dead fish in their tanks, it's a red flag that they might not be the best place to get your fish.
Ultimately, buying fish from a store with dead fish in the tank is a risk to the health of your existing fish and to the new fish you're bringing home. It's always best to choose a store with a strong reputation for caring for their animals.