The Beginner's Guide to Stocking a Smaller Aquarium/Fishtank

Stocking options in a desktop aquarium are quite limited, and a bad fish choice will most likely result in a dead fish within weeks.

FIRST AND FOREMOST: NO GOLDFISH.
Goldfish are probably one of the worst kinds of fish that you can get for your small fishtank. They are relatively messy fish who produce a lot of waste, and they live for decades and grow to sizes as large as one foot. What most people don't understand is that goldfish need a LOT of their own space. Not even a 5 gallon should be used to house a single goldfish.

Good types of fish are chosen based most importantly on their hardiness, their adult size, their acceptance of a wide array of water conditions, and their relative ease of care.

Male Bettas - These are probably the most common fishes kept in smaller bowls and tanks, because they are a type of fish with the ability to gulp air, and so they don't need any air pump or agitation of the water. Bettas will undoubtedly kill eachother, so only ONE betta can be kept in each tank. Bettas are treasured for their long, flowing, colorful fins.

African Dwarf Frog- Not a fish, but a very interesting animal nonetheless. A fully aquatic frog, the ADF stays at the bottom of the tank and surfaces regularly to get air. They are very comical creatures and are entertaining to watch. A bit harder to feed, because ADF's are not good at finding their food and other fish might steal their food before they get to eat anything.

Several types of hardy tetras, including the glowlight tetra, the black skirt tetra, and the prestilla tetra. These fishes are small, but they sport robust colors and enjoy the company of eachother. Tetras should be kept in groups of at least 4 of the same species. Neon tetras are commonly purchased, but they aren't the hardiest tetra and should be avoided by any beginner.

Endler's Livebearers- A very small guppy-like fish. Harder to find in stores. A local fish store may stock them, but petco and petsmart are very unlikely to. These fishes are extremely colorful. The males are black, orange, red, yellow, and green all in 1 inch of fish. They are a schooling fish so they should be kept in groups. They can be bought on the internet at aquabid.com or on several aquarium enthusiast forums. This fish is notorious for reproducing like crazy, so it is unwise to purchase males and females in a small environment. Stick with males--they are vividly colored. A recommended ratio from males to females is 1 male to 2 females in a larger tank; an even ratio would result in males competing with eachother for females. Note that you will need to do something with the fry, as you'll undoubtedly have many baby fish in about a month. You can sell them to a local fish store for about 1-3 dollars each if you raise them to adulthood, or you can feed them to larger fish if you have a larger fishtank.

Ghost Shimp-these are easily found in petstores. They take up very little room and produce very little waste, and they are interesting to watch. They eat leftover food from other fish or specially made pellets for shrimp.

White Cloud Mountain Minnows- These are quite possibly the most foolproof fish there is. They tolerate an extremely wide range of temperatures and pH.

Stocking options organized into the size of fishtanks:

1 Gallon:
1 Male Betta.
1 ADF

2 Gallon:
1 Male Betta and a few shrimp.
1 ADF and a few shrimp.
3 MALE Endler's Livebearers

3 Gallon: (you can add a few shrimp to any setup from this point forward)
1 Male Betta and 1 ADF
2 ADF's
6 male endler's livebearers
4 Hardy tetras
4 White Cloud Mountain Minnows

For larger fishtanks, you can add about 1-2 more fish per gallon of water. Note that fish should be the same species, as they feel more secure in a group of their own kind.

For more information on small aquariums, check out my other articles.