Some fish like guppies and goldfish are seen in every store.
Personally I don't like them because they are way to easy and everybody has one and they are just everywhere.
Datnoids ( tigerfish) are kept by everyone. There are many forums out there with hundreds of people who keep these. Most people don't talk about them on here but go to the more predatory fish sites and you'll hear about them all the time.
Endlers usually aren't seen because theya re more of a season fish and everybody screws the whole species up by breeding them with regular guppies so there are a lot of inbred hybrids out there that most of the time you can't tell the difference. Plus if you buy the actual endler pair at an
lfs there are very expensive...heck I could get 3 dozen feeder guppies and end up getting 10 of them...feeder guppies being 10 cents each so yeah theats a lot cheaper. When I tried getting a pair the company said they were a season fish, males ( or I think it was females) were only available at certain times. The
lfs accidentally ordered them thinkning I said yeha i want them..they ended up geeting about 10 males when it said 5 PAIRS of endlers.
I've seen and kept paradise fish, supposedly yeah they were the first imported tropical fish and were the second most popular fish, only being beaten out by the goldfish.
Here's some fish that I find most people have never even heard of or are so stunning or cool but nobody bothers with them:
Leopard ctenenopa ( spelling?) I have seen people keeping these (like fruitbat) but not many. Theses are very beautiful and inexpensive fish.
Needlenose fish..once again some people on here have them also. I have a one right now and have had some in the past, also look in my sig for my plans. Personally these are some of my favorite freshwater fish. I see them in a lot of stores lately but the
lfs people say that they never sell these.
African butterfly fish: a very beautiful and hardy fish. These are a perfect addition to almost any tank but haven't heard of many people keeping them.
Freshwater lionfish, hijueta gars ( actually characins), and apistogrammas are some others.
Sorry about the long post!