Colony Breeding: The Easiest Way to Breed Livebearers for Profit
Breeding livebearers like guppies, mollies, and platies is not difficult, and many hobbyists joke that all you need to do is add water. But what if you want to produce large numbers of fish to sell for profit at your local fish store or aquarium society? In addition, what if you are limited by budget or space and cannot afford to set up tons of tanks or giant ponds like the commercial farms? Keep reading to see how we’ve produced hundreds of livebearers in a single fish tank with minimal effort and cost.
1. Pick Your Starter Fish
Most people get fry because their pet fish “accidentally” bred and some of the babies survived. However, if you are looking to supply the local market with a high-quality product, make sure you start off with the best and healthiest parents possible. Look for fish with the ideal colors, patterns, shape, and size. Examine them from both the side view and top view to spot any defects like bent spines, missing fins, or drooping tails. Finally, get a ratio of one male for every two to three females. The bare minimum you should start with is a trio of one male and two females, but you will be more successful if you can start your breeding tank with six, nine, or 12 adult fish instead. Greater quantities not only increase your fry production from the beginning, but they also decrease stress on the females so that they are not constantly hounded by the males.
For some species like Endler’s livebearers, the females aren’t as colorful as the males, but aim to have at least 2–3 females per male to produce greater numbers of fry.
2. Set Up the Breeding Tank
The method we are going to use is called “colony breeding,” where the babies grow up in the same tank as the adults. Yes, you can get higher numbers by raising the offspring in a separate aquarium, but that requires more tanks, more aquarium equipment, more space in your room, and more time spent feeding and cleaning tanks. This setup has slightly less output but is one of the easiest techniques if you’re short on time or funds.
Remember that our goal is to build a money-making machine, not a gorgeous display tank. Adults will prey on their young, so we need to fill the aquarium with large amounts of algae, thickly grown plants, or even Easter grass. The tight spaces between the dense vegetation or material allow the young fish to escape but are too small for the adults to easily reach. They also allow females to hide away for a bit to get a quick break from the males. The goal is to have so much cover that you cannot clearly see the middle of the mass. Our preferred type of cover is live aquarium plants because not only do they offer shelter, but they also look naturally beautiful and help purify the water by consuming toxic ammonia from your fish’s waste. Our favorite plants for breeding fish include water sprite, Pogostemon stellatus 'octopus,' and java moss. For more ideas, read our article on the top 10 aquarium plants for breeding fish.
Ideally, the plants should be so thick that you can barely see through them.
The most popular livebearers available at the pet store often come from tropical climates, so you may need an aquarium heater if your room temperature is below their limits. In some cases, raising the temperature can increase metabolism, encourage more breeding, and speed up fry growth, but be careful not to heat the water so much that it shortens the fish’s life span. Another useful piece of equipment is a filter to help clean the water. We always use sponge filters in our breeding tanks because they have gentle flow, provide more oxygen to the water, and won’t suck up the babies. If you are using a hang-on-back or canister filter, make sure to cover the filter intake tube with a pre-filter sponge so fry won’t accidentally swim up into the motor.
Most livebearers live in harder, alkaline water, which is why many fish farms breed their livebearers in cheaper brackish water (a mixture of fresh tap water and ocean water) that has high pH and GH. But when customers take the fish home and put them in purely freshwater tanks, they end up going into osmotic shock and having massive health issues. To produce high-quality livebearers that are raised only in fresh water, we don’t recommend adding salt to your tank because then the fish will be harder to sell to local hobbyists and live plants won’t be able to survive in high salinity. However, if your tap water is very soft, we do recommend dosing mineral supplements like Wonder Shell or Seachem Equilibrium to prevent the fish from having problems with livebearer disease or the “shimmies.”
3. Overfeed the Tank
In general, you want to feed small foods that spread easily throughout the tank so that the fry don’t have to leave their safety zone among the plants or get outcompeted by the adults during mealtimes. Our favorite foods for young livebearers include live baby brine shrimp, crushed flakes, freeze-dried tubifex worms, frozen mini bloodworms, daphnia, and Easy Fry and Small Fish Food. The key is to heavily feed the tank — preferably with multiple feedings throughout the day — to boost the breeding and fry growth rates. Plus, it helps keep the adults fuller so there is less predation on their offspring. We like program an automatic fish food feeder to go off several times a day while we’re at work, and then we personally feed the livebearers once in the morning and once at night to observe their condition.
An auto feeder helps to ensure your fish get fed and continue growing, even if you are too busy or forget.
Water quality problems can quickly arise if excess fish food is left to rot in the aquarium, so make sure to adjust the portion size as needed and keep up on your water changes. For smaller livebearers like guppies, we’ve had success keeping Neocaridina cherry shrimp as the clean-up crew. Not only do they pick up all the leftovers, but they also serve as an extra source of live food for the livebearers. Plus, with all the hiding spots that you’ve provided the fish fry, some of the shrimp babies will survive and may become a second source of income that you can sell to your local fish store. If you prefer snails over shrimp, they are also excellent scavengers that can help pick any extra crumbs.
4. Cull When Necessary
As a conscientious breeder, you have a responsibility to not sell undesirable fish to your customers, especially if they can cause health issues down the road. Therefore, it is necessary to regularly cull or remove unsuitable fish from your breeding pool. Some of the offspring may have bent backs, missing fins, or other unwanted genetic traits that should not be passed onto the next generation. You should also repeat the culling process every few weeks since some defects may not show up until the fry are a little older. Because the breeding tank you set up is such an ideal environment for raising fry, you will need to remove the culls before they reach sexual maturity, which can be quite early for livebearers. This practice also ensures that the remaining healthy offspring receive more food and have the best chance of survival.
Culling fish can be a time-intensive process since you must carefully examine each fry for any defects.
There are many other methods for breeding livebearers for profit, such as catching out the females and putting them into their own separate tanks, but colony breeding is easier to maintain, especially if you are limited on money, space, and time. Each strain of fish only takes one aquarium, so you can potentially enjoy multiple varieties of livebearers at the same time while still maintaining the integrity of their lines. To learn about more best practices, check out our library of articles on breeding fish.