Livebearers are becoming more Weaker


Livebearers are becoming weaker.

You’ll find many old magazines and books that describe how livebearers, such as Endler’s Livebearers and Guppies, are great for beginners. They’re tough. Although this was true once upon a time, many of these livebearers have lost their wild stock. Unfortunately, most livebearers are now mass produced. We all know that quality suffers when things are mass produced. Here are some tips that will help you succeed with livebearers, despite the new challenges.

How Livebearers Are Bred

Let’s first understand how most livebearers were bred. Livebearers are most commonly bred in warmer climates, even during winter. This is for economic reasons. Florida, Thailand, Hawaii are all popular spots for people to have a fish farm. A pond is all that is required to raise the livebearers. Place a large number of livebearers into a large pond. Then harvest them as they breed. This process makes it very easy to produce a very large amount of livebearers with much less work than aquariums.

These systems can have many unfortunate consequences. The first is constant inbreeding between the livestock. There is no way to control the breeding of siblings or children, and genetic defects can spread unchecked until they are sold to wholesalers. Each farm will have its own way of breeding the fish. Some use cages to prevent culls from breeding etc) Many fish farms now harvest the fish from the ponds and then select quality specimens from sorting tanks in a warehouse. Even though they may look good, their genes can be affected. To illustrate the point, all “potbellied” variety of platies, and mollies are genetic deformities that have been commercialized and become popular in the trade. These were an accidental result of downbreeding.


The second problem with the pond style breeding is the introduction of parasites. While the farmers try their best to set up nets and keep pests out of their farms, the fish are exposed to outside influence such as bird parasites. This can have a devastating effect on populations of fish. Fish farms are quarantining the fish for a few days before shipping them out now to watch for parasites. However, if the fish isn’t stressed, they will be able to keep the parasite dormant. It is when the fish becomes stressed during shipping that the parasite is able to grab hold.

Breeding Facilities

Concrete is another problem. This causes the water to be contaminated with chemicals that can increase the pH and Hardness. Brackish water may also be used in place of straight freshwater for cost reasons. While this isn’t necessarily a bad thing on its own, uninformed stores and hobbyists are walking into a trap. The fish are coming from a high pH and hard water to local water tap conditions normally. This can put the fish into osmotic shock. Which can kill the fish in a few days or leave it very weakened for underlying conditions to finish it off.

Buying Livebearers

Now that we know how the livebearers we wish to keep are bred, what can we do to combat this? One option is to buy locally bred fish. Even if their stock came from a fish farm, the fry will at least avoid osmotic shock from the huge change in water parameters.

Wild Livebearers

Another option is to acquire wild livestock. These animals will be genetically more pure. These will not help you with “Fancy strains” of livebearers. However, they could still be susceptible to parasites and/or experience osmotic stress. It is worth considering whether or not the species may be endangered in the wild. Some aquarists intentionally breed wild, endangered fish to up the populations while others avoid them in hopes of keeping more in the wild.

Mimic Natural Water Parameters

This is the option most people choose. Setup your aquarium closer to the breeder’s water parameters.

It was accidental at first. Mollies were one of the first fish to be severely mass produced and hybridized to get all the great colors we have today. As a result, those mollies didn’t live very long. Breeders quickly found out that mollies can live in brackish waters after searching for the information. Many stores and hobbyists soon added aquarium salt to their tanks to make their tanks brackish. Amazingly, the Mollies did even better. We thought we had figured it out, but some people were using Aquarium Salt and others were using marine salt. It was the marine salt minerals that gave us the greatest benefit.

Keeping Livebearers Healthy

The battle plan to keep healthy livebearers coming from a fish farm starts with setting up your aquarium for the right pH and hardness of water. Then find out what day your local fish store receives fish. Acquire your fish ideally before they go into the store’s tanks (assuming your local fish store are not livebearer nerds who already set up these types of conditions), take them home and quarantine them in your own setup pH and hard water. Once they are acclimated, they will thrive. You can then, every so slowly, bring them down to the pH of your tap water over the course of months. You’ll eventually have fry, and they will have never seen anything else than tap water. Then you can provide your hobbyists with a stable livebearer.

The trick to the common day livebearer is to minimize stress so that our super colored, extra long finned, genetically down bred fish don’t have to test their immune system. Each new strain of livebearer brings its beauty and deformities with it.

I hope you get a tank ready and give livebearers another chance. They are my favorite type of fish to work with. Once they have been stabilized, they can last for many generations.