Q: How soon can Guppies multiply?
Females mature at about 3 months of age, perhaps sooner in a warmer tank. Males sexually mature somewhat sooner. If left in the tank together, the males will develop a modified, pointed anal fin called gonopodium at about 6 weeks, impregnate a female his own age, and a month later there will be only one or two young, since the fish are so small. The fry are normally not eaten since their size is so close that the parents! This is a good reason to separate them before the male can develop his gonopodium. When breeding fish, you want a large drop so that you can choose the best of them and cull the rest!
Q: Is my Guppy pregnant?
If your female has been around other males then chances are she is pregnant. It is rare to get a virgin female from any store tanks--if she is, she is probably not able to get pregnant. Signs of pregnancy are a large belly, a boxy-look from the front view, and a darker gravid spot. The spot, under the fish's tail, is like a stained-glass window where the fry come out. Near the day of delivery you can sometimes see eyes of the unborn fry as tiny black dots.
Q: When will my Guppy have her babies?
There really is no telling. You will just have to keep a close eye on her as she gets larger and her gravid spot get darker, because there are no definite signs. Sometimes a female will become rather still and solitary near birthing. If you know when she had her last drop, you can expect another drop in about 4 weeks or so.
Q: How do I save the fry?
The best way is to have a separate tank loaded with fake or live plants and a small box filter. Before the female is to deliver, put her in this tank, and when she drops the fry will lots of cover in which to hide. The mother will almost always make a meal of them if she sees them, since she is very hungry, and Guppies are naturally cannibalistic. Imagine how many Guppies there would be if they did not keep the population down this way!
Q: How and when I can tell the sexes apart?
The answer is, in a week or so, believe it or not! Just look for the gravid spot which every female has. Use a small glass and a flashlight. When separate them, if there is a question as to whether a Guppy is male or female, put it with males.
Q: How can I make sure who the father is?
Since a female stores sperm and had drop after drop (often 4, sometimes 8!)from just one fertilization, it is impossible to know if you have bought a non-virgin female. If the female is fertilized again at the time she drops her young that male's sperm should take over and the next drop should be his fry.
Q: What kind of home does my new Guppy need?
Many people new to Guppies look at the fish, buy one and think a fish bowl of 1 or 3 gallons is sufficient. However, this is incorrect.
A Guppy is very active and needs space, and space also give you the benefit of seeing the gorgeous colours of the fish in all their glory. Also, they are social fish and it is a sad injustice to submit one to solitary confinement. A group of three, a male and two females is the bare minimum, and for this one needs at least a 4 to 5 gallon tank.
Q: Does that mean a large investment then?
It is not necessary to spend a lot of money on a Guppy set-up. All that is needed is a tank (to start, I suggest a 10 or 20 gallon as there is more room for errors than in a smaller one!), a filter, and possibly a heater! Some people find great bargains on second-hand fish tanks and accessories. Remember that the larger the tank your fish have, the better, so get the largest you can afford.
Q: What plants or decorations do Guppies need?
Guppies do not need plants or gravel. They don't even need a wiz-bang heavy-duty filter. An inside box filter powered by a small pump is all that is necessary for biological and mechanical filtration and aeration (for a 5-10 gallon tank). You can leave out the charcoal and weigh the box down with your kid's marbles (after a good rinsing!). Paint the outside bottom of the tank with a dark paint (usually this is black). This gives a smooth bottom for the Guppy arena and no small stones will gather debris or leftover food where the Guppy cannot retrieve it. Also, it is more comfortable for the Guppy to rest at night on a bottom of smooth glass than a bed of gravel! This is the cleanest possible way to keep Guppies.
Q: How soon after setting up a new tank can I add fish?
An aquarium takes 6 weeks to cycle in order to be safe for a full stock of fish. To help, you can: Add a bacterial supplement such as Cycle, provide extra areation (water surface agitation), remove 5-10% of the water daily, add only a few inexpensive fish at first, and then slowly add more.
If you already have a cycled tank and want to set up another, you can instantly cycle it using 50% water from the cycled tank and used filter media in the filter. For more information on cycling, there is an informative link in the links section.
Q: What kind of filter should I use?
A 10-gallon tank can have a large-size box filter or an outside power filter, and anything larger than a 10 should definitely have a power filter. The filter I recommend is the Aqua Clear. A mini is sufficient for a 10 gallon, and the 150 is excellent for a 15 or 20-gallon tank. There is no need to constantly replace filter media, the foam should last years( rinse only in tank water), and once again, carbon is unnecessary as a medium. You may want to add an airstone in the case of power filters, as they do create some aeration, more is usually better.
I personally frown upon undergravel filters even if you have decided to use gravel for plants or esthetic purposes. They cause problems when you clean them and they are really not enough to keep a tank clean and when used in addition to an above gravel filter, they are in an over-kill situation anyway.
Q: How often do I clean the filter, and what is the best way?
Inside box filters should be cleaned when they start getting brown throughout the floss. It depends on your number of fish per gallon and tank maintenance how often this is, but it should not any more than once a week.
Remove the filter and change MOST of the floss. Carefully keep a small portion of the used floss and insert this between the new floss to retain some of the good bacteria and to help 'seed' new media. This is the best way to keep the essential nitrifying bacteria that breaks down the ammonia which is produced by fish wastes. If you keep carbon/charcoal in your filter, it should be rinsed with tank water (the chlorine in tap water destroys the bacteria) and replaced monthly.
Power filters should have their media rinsed weekly, and they should be removed from the tank and cleaned thoroughly, once, avoiding contact with chlorinated water.
Q-Tips, small toothbrushes, and pipe cleaners all make excellent tools for cleaning the parts of filters.
Q: Do I need a heater?
Heaters can be rather expensive, so this is a common question. Usually, the answer is "yes". A Guppy should have a temperature in the mid 70's F. If the temperature drops at night any more than 3 degrees, I recommend you use a heater. Drastic drops in temperature are stressful and eventually can cause problems like ick or fungus. If your normal day time temp is, for instance, 82F (too warm)and the temp drops to 76F at night, you may want to make sure the temp drops only 3 degrees or so at night with your heater.
Q: How often should I feed my fish?
Fry should be fed several times daily (see page on Fry)
Adults should be fed less, with a diet lower in fat. Two or three times a day is the maximum for mature fish, and the feedings should be rather small.
Q: Can I sell my extra Guppies?
There are some smaller pet stores that will take in Guppies, however, many do not.
It isn't a good idea to raise Guppies with this intention, because you only get about 1/3 of the selling cost of the fish (this is only about $1 a fish usually). They must be close to maturity as well, and it is hardly worth the expense and effort to raise Guppies for this purpose. If you simply have too many it is a good place to drop some off though.