...keeping is one of my hobbies. I used to keep them when younger because my uncle was a great fish keeper. He taught me a lot of what he knew. Of course, I also keep reptiles & amphibians and that is also mostly due to my uncle because he bought me my first Red Eared Slider Turtle. I wound up getting away from the fish for the most part, although I did keep some on and off over the years; usually for food for my turtles or snakes but sometimes for the sake of keeping fish. Then I got back into keeping them, maybe a year or two ago, for the sake of being a tropical fish hobbyist once again. I had decided to keep less reptiles and delved into amphibians, specifically newts and aquatic salamanders and figured that fish would go well with them. Or was it the other way around, maybe I got the fish first - oh it doesn't matter.
Anyway, I now have one semi-aquatic tank set up for fish and frogs, one tank set up for my turtle and fish (it was not meant to hold fish but two feeder goldfish survived until they got too big for the turtle to chase down and make a meal of so they are living large in the turtle tank), one tank of aquatic salamanders (no fish), one tank for several Blue Tailed Fire Bellied Newts, a couple of Gold Mystery Snails, a few Green Aeneus Catfish and several guppies, and a tank with virtually all tropical fish save a single Iberian Ribbed Newt that shares their tank.
The one tank with mostly tropical fish holds: 5 Paleatus Corydoras, 2 Pictus catfish (often mislabelled as Angelicus Cats), 2 Kribensis, 3 Rams, 1 Cardinal Tetra (used to be about 5 or 6 but the Pictus catfish got the others, the remaining one is now too big for them to gobble up), several guppies (plain, more or less feral and not one of the many varieties with fantails), one Golden Algae Eater and a Gold Mystery Snail. I would love to get myself several more cardinals but they have been hard to find in good health. The only times I have seen them over about the last year, and they are scarce in pet shops and aquariums up this way, they have been emaciated looking and in water that has been treated with medicinal chemicals. (Anyone know the reason they all seem to be in bad shape? If so please leave a comment or email me with info.)
I have been hoping to breed the Aeneus corydoras and the Peleatus corys too. The green Aeneus cats have often laid eggs but none have ever been fertilized although I am sure I have at least one male in the group. As for the Peleatus cats, they laid eggs once, all were fertile, but all were eaten by tank mates. Since then, probably over a year ago, they have not bred again. I'll have to read up on them a bit and condition them properly to induce breeding, they are nice fish. As for the Kribensis, I am surprised they have not bred as all is as it should be for them to do so. I have a definite male and female in the community tank (they often breed in community tanks) but I may put them into a tank of their own to see if they will mate.
On the whole, tropical fish are fun to keep, interesting too. They are not difficult to keep once you get the hang of it, especially if you start with a large enough tank (at least 30 gallons - makes it easier to maintain good water chemistry with a larger tank, larger than 30 is better yet) and fish that are on the easier side to keep. Note they don't have to be drab or plain to be easy to keep, fish like Kribensis, Rams, Cardinals, Pictus cats, Algae Eaters, Guppies (even the fancy ones) and all virtually all of the Corydoras catfish are pretty easy to keep. If you are looking for a hobby, that is fun, interesting and does not cost an arm and a leg (initial costs are moderate fairly high, compared to other pets, for a complete set-up, but after that costs are usually low to moderate depending on your tastes in fish or if you expand to more tanks) I highly recommend tropical fish keeping.
All the best,