Guppies have been a favorite of mine since I was really young. I remember having a fish tank full of guppies when I was younger. I started out with one male guppy and a couple of female guppies. After a few months my aquarium was full of so many guppies, I didn't know what to do! It was fun to watch as more and more guppies populated my aquarium because of the constant breeding taking place. Guppies are relatively easy to care fore. I keep mine in a 20 gal aquarium with quite a few plants. It is really fun to watch them swim through the leaves of the plants and watch them interact with each other.
Tank Size: I don't like to keep fish of any kind in an aquarium smaller than 10 gallons. The smaller your aquarium is, the faster it gets dirty, and the easier it is for fish to get sick. Guppies do well in a 10 gallon aquarium or larger. A good rule of thumb with any fish is 1" of fish for every gallon of water. I have a 20 gallon aquarium with over 20 guppies and 4 kuhli loaches. This is probably overstocked, and that is why I have 3 filters. I have extra filtration to make up for the extra waste produced by so many fish. I also make sure to do weekly water changes of at least 10%. Removing water from your aquarium and replacing it with fresh water helps to remove toxins from the water that your filters can't break down. If you want to play it safe, you should just stick to the rule of 1" of fish per gallon of water.
Diet: Guppies readily accept flake food. A good quality flake food is a good staple for guppies. To supplement their diet and give them necessary nutrients, I occasionally feed them brine shrimp and blood worms. Brine shrimp can be bought frozen or you can hatch them yourself. Blood worms are available frozen at most pet stores.
Plants: Guppies can survive in an aquarium without any live or fake plants, but what a boring life for them! Live plants are not necessary for guppies, but they do provide the fish with a more natural habitat. My guppies love to swim through my plants and chase each other around. If you want your guppies to display their most brilliant colors and have a more interesting life, consider planting some live plants in your aquarium for them to enjoy. Aquatic plants can be a bit pricey if you buy them from a pet store or an aquarium supply store, and they might not be very hardy. I recently bought some live plants from an aquarium that wilted and died within a few weeks. These plants usually require a very bright light source and a supply of CO2. A good alternative that I have found is pothos plant. You can purchase a large pothos at a local home and garden store for around ten bucks, and you can snip off portions of the plant and re-plant them in your aquarium. This plant is not naturally aquatic, but I have found it to take very well to the water and be very hardy. It a bright green color with broad leaves which provide your fish with places to hide. I think this plant produces a pleasant natural look in an aquarium.
Sexing: Males and Females are very easy to tell apart. Males are smaller than females and have longer more colorful tails and fins. Females are larger, less colorful and have much rounder bellies than males. You can also notice the gravid spot behind the belly of a female.
Breeding: Guppies are one of the easiest fish to breed. All you need is a male and a female and they do the rest! You don't have to do anything special to get them to spawn. Guppies are live bearers which means that they give live birth and do not lay any eggs. Once the parents give birth, it is necessary to remove all of the fry (babies) from the aquarium and move them to an aquarium without any adult fish. This is because the adult fish mistake their tiny babies as food and withing a couple of days, all of the fry will be eaten up! You can tell that a female guppy is pregnant when you see a large dark spot behind her belly (gravid spot) and she gets really plump. This gravid spot is where her eggs are and it gets really dark when she is about to give birth. It gets dark because of the eyes of the developing fry. You may want to move a pregnant female to a separate aquarium to give birth, and then move her back to her original aquarium so she doesn't eat any of her babies. This will be much easier than trying to locate and capture all of her tiny, hard-to-see babies from an aquarium already full of fish.
Fry Care: Move fry to a separate aquarium so they aren't eaten by any adult fish. Once fry are born, they are ready to fend for themselves! There are specialized fish foods sold at pet stores that are finely ground small enough for your fry to eat. You may also want to hatch some brine shrimp for them to eat. Brine shrimp eggs are readily available at most aquatic pet stores, and they are relatively easy to hatch. Brine shrimp are high in protein and small enough for your fry to eat when the shrimp are just hatched. I feed my fry a diet of finely ground flakes and brine shrimp together to make sure they get their necessary nutrients. Fry will grow pretty quickly, and you can move them back into your main aquarium within a month or two. If you are not too concerned with saving all of your fry that are born, you may want to let them fend for themselves in your main aquarium when they are born. If you don't have any live plants or places for them to hide, they will most likely be eaten up in the first few days of their life. If you have lots of plants and hiding places, a few of them might survive and grow to adulthood. Right now in my aquarium there are a few fry that were born about a week ago, and I can see that three of them are still surviving. Most of their siblings have already been eaten, but these three are really good at hiding. I have seen them being chased by one of my larger fish, and they can get away to survive because I have so many plants for them to quickly hide in.
Here is a shot of one of my fry hiding in some plants.
Pictures
Another picture of "Leopard Spot", and a couple of my females.
