Freshwater Fish and Resources
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The BioSierra Catalog
One person and one web page can not begin to cover all of the material you should be considering when you work with Livebearers. With that in mind, we would recommend (very highly) that you consider the material presented here as a "primer" and a place to start rather than a place to stop. An excellent source of material on Livebearers is the web site of the American Livebearer Association.
How to Tell Males from Females
Giving Birth
General Breeding Considerations
Taking Care of Fry
The Big Four
Platies
Swordtails
Guppies
Mollies
How do I take care of livebearer fry?
Some general consideration that would apply to most fry also apply to the fry of Livebearing fishes. All fry are sensitive to being moved from one container to another for the first few days (or more) of their lives. So it is important that you plan for the birth and give them a good start.
Feeding the fry is an important consideration. Most fry from Livebearing fishes will take flake food from their first day (particularly the top feeding livebearers with up-turned mouths). Frequent feeding is preferred to once a day feeding. Remember that the fry have small stomachs and feed them appropriately sized foods. You can grind up standard flake foods into a powder to create a food fine enought to feed...we use the palm of our hand as a mortar and our fingers as a pestal. You will find literature that recommends you feed the fry upwards of 6-8 times per day. While perhaps an ideal frequency, the practical application of the schedule is very difficult. We find that feeding a couple times in the morning and a couple more times in the evening with the feeding spaced perhaps an hour apart will give the fry a pretty healthy amount of food.
Most livebearing fish drop fry that are large enough to eat baby brine shrimp or microworms from the first day. We recommend that you consider either of these two foods. We have had fantastic growth when combining the live foods with a balanced diet, as compared to the prepared foods alone. We understand the extra effort that caring for and harvesting the live food presents to most hobbyists. However, we also know just how easy microworms in particular are...you should think about it.
Don't over look the importance of regular water changes. For all of the same reasons that you need to change the water in the tanks of the adults...the changes in the fry tanks is equally important. Even to the casual observer, the growth of fry in the first weeks of their lives is enhanced if water is changed on a frequent basis. We change 50% of the water every day, siphoning ditritus from the bottom of the tank.
We like to use mature sponge filters in each of the fry containers. Not only will the sponge provide media for the bacteria to live within, but the sponge will probably house a healthy colony of rotifers and other infusoria...both excellent food for the young fish.
When the fish are large enough not to be consumed by their parents you can probably add them to the tank with the parents. However, not all Livebearers are peaceful. Some are downright mean to any fish smaller than themselves...Gambusia coming quickly to mind...so use some common sense and draw on the research you have done on the particular fish you are working with to determine when to add the fish back into the tank with the parents.
If you are going to be involving yourself with a serious breeding operation with guppies you will need to have several tanks. Not because of the volume of fry, but more to separate males and females and young from the breeders.
How Can I Tell Male and Female Livebearers Apart?
The common livebearing fish are easily sexed through observation. In some fish there are obvisous differences in the outward appearences. For example, dominant male swordtails have swords on their tails while the females do not. In some species, the male fish is much more colorful that the females...guppies and Endlers for example. For the more common livebearers, one of the best observations is focused on the anal fin, that fin furthest back on the belly of the fish, just in from of the tail.
Generally speaking, the anal fin of adult females is fan-shaped. On mature and/or dominant male, the anal fin is tube-shaped. For common livebearers the modified fin is called a gonopodium and is used to deliver sperm packets to the female. There are several variations on this anatomical structure, but generally, it is fairly obvious.
How Do I Know When My Female Livebearer is Ready to Give Birth?
The most common of the livebearing fish can drop a new group of fry every four to eight weeks depending on diet, temperature, and other conditions. When the female is ready to deliver, the gravid spot (a triangular-shaped area just above and behind the anal fin that turns darker as the delivery date approaches) will be well developed. Now there are exceptions to the gravid spot rule, X. "nezzy" being one of them...the males can show what will resemble a gravid spot. Many livebearers (most of the light bodied swordtails for example...and many of the goodeids) will show a darkened area whether they are holding fry or not.
We like to keep track of when a female last dropped her fry. If we are dealing with a species that will be dropping again in about a month, we remove the female to a maternity tank about a week before she is scheduled to drop again. Many livebearing fish are canabalistic and if your main tank is a community tank you will find that most fish consider fry a very tasty snack. We have found that the easiest and maybe the best drop tank is a 5 gallon or a 10 gallon tank with lots of cover for the female to feel comfortable and for the fry to hide in when they are dropped. We like to use Java Moss for the cover, but many fine leafed plants will work. At times we use yarn mops just as we would for Killifish. We don't like to use "breeding nets" or "breeding traps" as we have found that they are too small for most of our fish and seem to stress the fish. Besides, once the fry are dropped in the 5 or 10 gallon drop tank and the female removed, the fry can simply be kept in the drop tank for a week or two, giving them an excellent start.
We have found that most drops are in the early morning hours and may take several hours. We remove the female to a holding tank as soon as the birthing is complete. If you leave her in the tank, most females will try to eat the fry...and if you put her into the tank with the males they will immediately try to breed. We're not sure if the female needs a break or a rest, but the constant attention of the males just seems to be well...too much. We give the female several days to rest and eat without being harrassed.
How Can I Breed Livebearers?
Most of the common livebearers (the Big Four; swordtails, mollies, guppies, and platies) are fairly easy to breed. We have had our best success using trios (two females and one male). Males only seem to think of two things...eating and breeding. When the set-up consists of a low female/high male ratio the females will have a hard time even trying to eat and seemingly will never get any rest.
An interesting function of mating that occurs with many Livebearing fish is the ability to drop several batchs of fry from a single mating. Many times a solitary female will deliver fry for several month. The sperm is delivered in "packets" to the female and she has the ability to use them as she needs. It is this ability that makes the early separation of males and females important for a quality breeding program. Some of the fish become sexual active prior to the observable color distinctions. Many mongural fish are dropped by fish purchased in the fish shops...which accounts for the phenomion of orange fish being born to golden fish parents.
Not all livebearers are capable of this packet storing function. For the vast majority of livebeares it does not occur, but the Big Four are all capable of storage.
What Should I Know About Keeping Platies?
There are two common types of these livebearers: the brightly colored maculatus platy (the tuxedo, micky mouse, wags and such) reaches a size of about 2 inches and is usually not an aggressive fish. The variatus platy doesn't have as many color forms as the maculatus does, but it does come in some spectacular long-finned varieties. The recently available high finned varieties do tend to be a little more sensitive to water quality and also seem to be a little more desease prone. We have found that larger tanks and frequent water changes seem to mitigatet these situations.
Don't keep platies in anything smaller than a 10g tank. They are an active fish and don't do all that well in small tanks. If you can afford the space, a 20g would be better.
Swordtails will eat commercial flake foods and live foods. We feed our breeding stocks blackworms, grindal worms and fruitflies in addition to flakes. They also need to have some vegetable matter in their diet, so we add biweekly feedings of Spirulina based flakes. We also encourage algae on the sides and the back of the tank. The fish graze on the algae giving them a good source of plant material.
They are very adaptable to different temperatures, from the low 70s to the low 80s. We keep our tanks at about 75 F. The Ph of our system water is nuetral. Our water has a TDS of 110 ppm.
What Should I Know About Keeping Swordtails?
Most swordtails will grow to about 3 inches in an aquarium (not counting the male's tail extension), but I've seen pond-raised swordtails that were more than 5 inches in length. You probably should consider a bigger tank than you orginially planned on. Because swordtails should be kept in groups, we have found than a 20 gallon is just about the minimum for a group of 5 fish..and the fry will need to be removed from that. If you put them in a community tank, you will need to remember that these fish can suffer with mediocre water quality. The fish come from flowing rivers and streams (not lakes and ponds) and prefer clean water with frequent large water changes.
Some folks think that swordtails are rather combative and will attack one another in too small a space, but what they are probably witnessing is a male dominance pattern. Swordtails develop strict hiarchries in their communities...the alpha male will be the male with the largest sword and will defend "his" females in mostly ritualistic displays or aggressiveness. Keeping several females and a couple of males together in a larger tank will generally solve any problems.
Swordtails will eat commercial flake foods and live foods. We feed our breeding stocks blackworms, grindal worms and fruitflies in addition to flakes. They also need to have some vegetable matter in their diet, so we add biweekly feedings of Spirulina based flakes. We also encourage algae on the sides and the back of the tank. The fish graze on the algae giving them a good source of plant material.
They are very adaptable to different temperatures, from the low 70s to the low 80s. We keep our tanks at about 75 F. The Ph of our system water is nuetral. We sometimes find a group that prefers harder water and use the affluent from our RO unit to change water in those tanks. The resulting water will be about 7.8. Our water has a TDS of 110 ppm.
What Should I Know About Keeping Guppies?
The smallest of the "big four", guppies can be kept in smaller tanks...as small as 2 gallons for a pair. Some of the fancier guppy varieties have large tails that are an easy target for nippy types of fish, so if your are going to keep the long finned varieties in a community tank situation you will want to take a little care in selecting suitable tank buddies.
Guppies are one of the most commonly kept of the livebearing fishes. They range from cheap "feeders" to expensive "show quality" specimens. You will want to do some research about these fish before you simply pick some up at the local fish store. Great guppies are extraordinary...good guppies are barely comparible. Whatever you do don't underestimate the bueaty of these fish.
Like the rest of the "big four", guppies are very adaptable to different temperatures, from the low 70s to the low 80s. We keep our tanks at about 75 F. The Ph of our system water is nuetral. We sometimes find a group that prefers harder water and use the affluent from our RO unit to change water in those tanks. The resulting water will be about 7.8. Our water has a TDS of 110 ppm.
What Should I Know About Keeping Mollies?
In the wild, these freshwater livebearers live in areas that may be influenced by tidal action. For this reason, mollies are sometime more comfortable with a slightly brackish environment. Frequently you will find that they are more comfortable with a tablespoon of salt per gallon of water.
Mollies will eat commercial flake foods and live foods. We feed our breeding stocks blackworms, grindal worms and fruitflies in addition to flakes. They also need to have some vegetable matter in their diet, so we add biweekly feedings of Spirulina based flakes. We also encourage algae on the sides and the back of the tank. The fish graze on the algae giving them a good source of plant material.
The common short-finned mollies include the black molly, the gold-dust molly, and other varieties. They can exist nicely in a 10-gallon community tank and will do fine without salt in the water so long as the water is kept very clean.
Sailfin mollies are much larger and more spectacular than their short-finned cousins. They will grow to more than 5 inches long and should not be kept in tanks smaller than 20 gallons. They seem to be more sensitive to water quality than the short-finned mollies.
Like swordtails, folks think that male mollies are rather combative and will attack one another in too small a space, but what they are probably witnessing is a male dominance pattern. Mollies, like swordtails, develop strict hiarchries in their communities...the alpha male will be the male with the largest fins of the most striking color and will defend "his" females in mostly ritualistic displays or aggressiveness. Keeping several females and a couple of males together in a larger tank will generally solve any problems.
Mollies are very a little less adaptable to different temperatures, and prefer warmer temperature than some of the livebearers from the highland stream. Consider keeping your Mollies in the from the mid 70 to high 70 F range.
After you have browsed the American Livebearer Association site (http://www.aka.org), perhaps even joining a local club...read through a couple of books...surfed the net until you need a new mouse...if all else fails, email us.
