I work at a PetSmart and pretty much wasn't allowed to answer questions about anything other than bettas and hermit crabs for the first week I worked there. I had bettas before and I had researched hermit crabs when I thought I was going to get some. Other than that I was pretty clueless. One of the first things they taught me is the PetSmart labeling system. The tropical community, semi-aggresive, SA cichlid, african cichlids, and goldfish all have different labels and shouldn't be mixed. I was taguht a few exceptions later on but at first they stuck to the basics. I pretty much shadowed one of the two experienced fish people for the first couple weeks. When there were no customers they taught me about tank cycling. I got my first 10 gallon soon after I started working there and they helped me with it. Later on they taught me about the special needs fish like pacu, needlefish, dragon gobies, knifes, etc. I also got a basic education about what cichlids go with which and how big oscars get. I was lucky. PetSmart doesn't allow enough training hours anymore for us to do something like that so our two new people sometimes make recommendations that aren't so great. At other PetSmarts I hear of people who obiviously either have no idea what they're doing or are just pushing sales. PetSmart provides materials to learn from that should educate these employees better. They are just choosing not to open up the binder that sits on top of every PetSmart fish podium in the country or take the time to read a few care guides. Some are surprisingly good. You still have to be taught about the few oddballs like dwarf puffers but the guides will at least cover some stuff like basic compatibility, tank cycling, and maintenance.
I was taught how to net fish by practicing on feeder fish. The only other thing I was really taught is that big nets make it easier and I need to use the very fine mesh pro-style nets on catfish that have spines like striped raphael and pictus cats. I was also taught to lift the big fish quick so that the customers and me don't get splashed as much.
I feed the fish with no problems and know most of their diets fairly well but when I first started I was constantly forgetting who got the frozen food and who just got flake. So I fed with one of the more experienced people for awhile. And most of the store managers had worked in fish before so I could run and ask them if I wasn't sure about a fish.
Now I can solve most fish problems I'm presented with and recommend compatible tank mates for most fish. Some of the cichlids I still have to guess at but I know the most common ones. I have helped a lot of people through cycling their tank and gotten a lot of prospective goldfish bowl owners to either get a betta and keep the water clean or even buy the $40 ten gallon kit we sell and give their fish a good home. And I've gotten a lot of people to steer clear of the common pleco, pacu, and oscars.
Fresh filleted sea bass is just about the most amazing food experience you can have. And by fresh I mean it was caught less than 4 hours ago and filleted right before it was cooked. I had that in Alaska after a fishing trip and it was one of the best meals I've ever had.

Not fishy at all. But I voted for tilapia because you can order it at a restaurant or cook from frozen and it's still good. Bass goes gross and fishy too fast to eat it other than very fresh caught. The water they are caught in is a big contributor to taste too in my opinion.