I've had those once. I found them creepy. :oops: They remind me of snakes. They were good at hiding. They are said to be a gentle species. Loaches are hard to find here too.
The goldfish life span is said to be 10 years to 60 plus. That being said I believe 12 years is a decent age for a goldfish. It's similar to how it's said chickens live to 10-15 years, but very few people see that. Goldfish will live longer in a large clean pond, but most people can't do that...
One does not need a college degree to keep goldfish correctly or understand diseases. I once worked in a pet shop as well. It did nothing for me.
Experience keeping goldfish and learning about their needs through experience, as well as doing lots of reading is how I come by my knowledge. In my...