Top 5 Easy Fish Breeding Ideas for Your Next 20-Gallon Aquarium

When our founder Cory first got into fishkeeping, funds were tight, so he started breeding fish to help with his hobby expenses. After many years of experience keeping fish rooms and tanks of all sizes, he still loves breeding fish at home in the versatile 20-gallon aquarium (both the high and long versions). Here are his top five favorite fish and invertebrates, which are easy to spawn in a colony environment.

1. Mouth-Brooding Bettas

Betta albimarginata

Most people know about Betta splendens with their large and colorful fins, but breeding them can be hassle since the male juveniles are too territorial to cohabitate and must be raised in individual jars until they reach a sellable size. Some mouth-brooding Betta species, however, are more peaceful and can be kept together in 20-gallon breeding sets. We have had great success keeping the strawberry betta, B. albimarginata, and Penang Betta (B. pugnax), however there are many other species such as the snakehead and rubra bettas (B. channoides). We like to cover the aquarium with thick hardscape and plant densely to create a break in the line of sight for future fry. It is recommended that you use a tight-fitting lid to keep fish from jumping out. For aggression-free swimming, small dither fish can be added to the tank such as neon Tetras. These bettas love acidic, tannin-stained waters so make sure to include catappa leaves and other botanicals.

After the eggs are fertilized and the female has borne their offspring, the male must keep the brood alive for the next 1.5-3 months. The male will let the babies swim once they have hatched. The fry can usually eat baby brine shrimp immediately after hatching. This superfood will allow them to grow fast and is extremely nutritious. Just know that the male cannot eat while he is holding eggs, so to prevent him from losing too much weight, put the female into a separate tank or breeder box until he has time to regain his mass before breeding them again. As the tank becomes more crowded, remove the juveniles to make room for the next brood and prevent territorial disputes.

2. Dwarf Shrimp

Neocaridina davidi

Dwarf shrimp is a good choice for breeding something that is in high demand and easy sell. There are many species to choose from – such as Neocaridina cherry shrimp, Caridina crystal shrimp, and even Sulawesi shrimp – so select a type that works best with your normal tap water’s parameters. Dwarf shrimp love to eat all the gunk and mulm in an aquarium. They do well in a tank that has been in good condition for several months. Although it is nice to have them in a planted aquascape, they will be happy eating the algae-filled food. For filtration, use a sponge filter with gentle flow (or put a pre-filter sponge on the intake of your hang-on-back or canister filter) to prevent any tiny babies from being sucked up.

If your goal is to produce as many shrimp as possible, then keep a species-only aquarium with no other tank mates. However, if you want a livelier aquarium, then you could add other nano fish like chili rasboras and green neon tetras. You can feed them a lot to make sure they don’t eat too much and give the babies shrimp more places to escape. For more ideas, read our article on the top 12 tank mates to keep with dwarf shrimp.

3. Fancy Guppies

Poecilia reticulata

Fancy guppies are another aquatic animal that is very popular and easy to breed. As with most livebearers they need good water and food to reproduce. Parents will predate on their young so add plenty of plants such as water sprite or Pogostemon.stellatus “octopus” to increase the number. The babies can hide and adults have a harder job reaching them. Either you want to breed a tank with random colors or a single pure color. In both cases, be prepared to cull the fry and remove any young that show deformities or throw undesirable features that would mess up your line breeding efforts. Read the entire article for more information on colony breeding livebearers, such as guppies.

4. White Cloud Mountain Minnows

Tanichthys albonubes

Many hobbyists view egg layers as more difficult to breed and raise than livebearers. Therefore, white cloud minnows make a great starting fish. Cory bought a few of these fish as feeder fish and was shocked when he accidentally bred several. Encouraged by his success, he went on to run the “White Cloud Race” at his local fish club where contestants would start with six minnows and see how many they could make over the summer season. This fish is very easy to care for and can be kept outside in mini-ponds during the summer. You can raise the fry in the same colony as the adults, provided you don’t have any snails or fish. The older juveniles will often prey on the younger ones, so make sure to have plenty of shelter, and move the teens out. Learn more about how to care for them and what color variations they have.

5. Desert Gobies

Chlamydogobius eremius

You might feel like you know how to breed all the most common fish species after years of fishkeeping. What oddball fish are you able to breed that is still reproducible? Meet the desert goby. While it’s not the most colorful fish out there, we love their unusual appearance and unique behaviors. Although they can be kept in community tanks, most of their babies will end up as food. We prefer to keep them in a species only setup for breeding purposes. They have large mouths and can get a little territorial during spawning seasons, so provide lots of hides for the subdominant adults. A 0.5-inch (1.35 cm) PVC pipe can be added to encourage breeding. Watch them lay eggs inside. When they hatch, you will see tiny fry crawling on the ground. They aren’t as high-yielding as livebearers so don’t expect to build a huge colony, but they are a really cool fish that many people haven’t played with before.

We wish you all the best with your next 20-gallon breeding endeavor. You can view the stocking list of our favorite online retailers to see what is available, even though we don’t ship live fish. For more tips and tricks, check out our favorite articles on breeding aquarium fish.