How to Care for Guppies

Guppies are among the most colorful freshwater tropical fish in the world. They are small and relatively low-maintenance, making them perfect for beginners who are just starting to set up a fish tank or learn how to care for fish. With the right tank setup, a proper diet, and careful attention, these fish thrive.

Choose the right tank. A 40-liter tank is the ideal size. You need a tank that isn't overcrowded. For example, if you're using a 40-liter tank, you should only keep around five guppies in it. This way, it’s easier to maintain the tank and keep your fish healthy.

• Some breeders and guppy enthusiasts may argue that the tank size doesn't need to strictly follow this guideline, but if you have a higher number of fish in the tank, you’ll need to clean and change the water more often. It's something to consider when deciding on the tank size and the number of guppies you want to keep.

Remove chlorine from aquarium water. There are several methods to eliminate chlorine from your aquarium water. One option is to leave the tank uncovered for about a week to let the chlorine evaporate, or you could purchase a chlorine remover. It’s essential to treat both the aquarium water and any additional water that you will add later.

• You can purchase chlorine removal kits at pet stores at a reasonable price. Additionally, it’s a good idea to buy a chlorine test kit to ensure there is no chlorine left in the water before introducing any fish. Follow the instructions provided on the product label.
• Tap water typically contains chlorine. You can use purified, filtered, or distilled water, which doesn’t contain chlorine, but it’s safest to check the chlorine level before adding fish to the tank.
• Aim to maintain the pH of the aquarium water between 6.8 and 8. Guppies prefer a higher pH, so if you plan to add crushed coral, maintaining a pH around 7.5 is ideal.

Maintain water temperature between 24-28°C. Place a thermometer in the tank to monitor the temperature. If necessary, you can install a small heater to warm the water.

• If using a heater, make sure it is appropriate for the size of your tank. For example, a 20-liter tank requires a lower wattage heater compared to a 40-liter tank. Ask the pet store staff for advice on which heater is suitable for your tank.
• To prevent the temperature from getting too high, avoid placing the tank in direct sunlight. Use the heater if you need to increase the temperature and rely on artificial lighting instead of sunlight. If the water becomes too warm, replace some of the warm water with cooler water to gradually lower the temperature.

Use a filtration system. Most aquariums come equipped with a filtration system. If yours doesn’t have one, you’ll need to purchase a separate filter. You should replace the filter when it turns brown, so make sure to check it every time you clean the tank. Ceramic filters are particularly effective for promoting beneficial bacteria, which help keep the tank clean and support fish health. You should replace only half of the filter at a time to avoid removing too many beneficial bacteria at once.

• If your tank already has a filter, you can upgrade to a better one if needed. Ensure that the filter system is capable of handling the number of fish and the size of the tank.
• A standard filtration system is sufficient for oxygenating the tank, but if you have a larger tank or more fish, you can add an air pump to increase the oxygen levels.
• The tank should be set up and running for about a month before introducing any fish. Resist the temptation to buy fish too early. Beneficial bacteria in the filter help break down harmful substances in the water, as the water will become polluted by the waste from the fish. These toxins can’t be removed by the mechanical filtration system; only bacteria can significantly reduce their toxicity. You can support this process by performing partial water changes weekly. During this month, feed the bacteria small pieces of fish food (one piece every three days) to help them adjust before you introduce the fish. This process is known as “cycling the tank.”

Add aquatic plants and decorations to the tank. Start by placing gravel or pebbles at the bottom of the tank. Stones or gravel are great for guppies. Then, add live plants. Using real plants is recommended as they help process toxins and provide beneficial bacteria. Another important consideration is that fish need hiding spots, as guppies often display this behavior.

• Be sure to wash the gravel and decorations thoroughly before adding them to the tank. You must remove any dust or dirt that may have accumulated on them during their time at the store.
• Avoid adding natural items such as seashells, tree roots, or sand, as they may contain parasites or alter the pH of the water (or generally harden the water if you add limestone). This could make the fish ill or even cause their death. It’s safer to buy these items from a pet store to avoid unexpected issues. Only experienced aquarium keepers should consider adding natural items, as they can distinguish which roots and stones are safe and which are toxic (they need to research and gather information beforehand).

Install lighting for the aquarium. It’s best for guppies to have 8 hours of darkness each day. Having too much or too little darkness may cause deformities as they grow. You can install a light above the tank and set a timer to ensure the guppies get enough light each day, or manually turn the lights on and off each morning and evening.

• If using natural light, such as placing the tank near a window or light source, ensure the light doesn’t significantly affect the water temperature. Always maintain the appropriate temperature for the guppies. However, natural light can lead to algae growth, so it’s better to use artificial lighting.

Provide the right type of food for your fish. You can feed guppies a variety of foods, both dry and wet, live or frozen. Pre-made fish food for guppies with balanced nutrition is available, but remember to avoid feeding them only high-protein foods. It's important to balance protein intake with vegetables.

• Saltwater shrimp, earthworm pellets, dry bloodworms, white worms, and mosquito larvae are great options to feed your guppies.
• Flake fish food is a good choice for their primary diet. Always read the product label before purchasing.

Feed small amounts multiple times a day, 2-4 times. Instead of giving them a large amount of food at once, spread the feedings throughout the day. Try varying the types of food you feed them each time. For example, one time you can give them live shrimp, and the next time, you can provide flake food.

• Be careful not to overfeed. Guppies should be able to consume the food within 2 minutes.

Monitor the digestive health of your fish. The condition of the water in the tank is a good indicator of whether your fish are thriving on their diet. If the water becomes cloudy or algae starts to form, it could be a sign of feeding issues.

• If the water in the tank is cloudy, reduce the amount of food by 20% for a few days and see if this helps the fish adjust and if the water naturally balances out. This may indicate an increase in toxins (ammonia and nitrites) due to skipping the tank cycling phase.

Maintain a ratio of two or three females to one male. It’s best to keep multiple guppies in the tank, as they are social fish and thrive in groups. Ensure the female/male ratio is 2:1, as males can stress out females and chase them around the tank. Keeping more females than males can help reduce this issue.

• If you don't want the fish to breed, consider separating the males and females. Guppies give live birth rather than laying eggs, so if they mate, you will quickly see baby fish.
• Learn more about breeding guppies before you attempt this.

Clean your aquarium weekly. This involves changing about 25% of the water with freshly dechlorinated water. You should also use a siphon to reach the bottom of the tank and remove leftover food or algae that might grow on the substrate.

• When cleaning your tank, avoid draining all the water and replacing it. Changing just 25%-40% of the water will help the fish adjust more smoothly.
• A filter can handle most daily waste, but using a siphon (which you can easily find at pet stores) to clean the bottom will ensure the tank stays cleaner and the fish stay healthier.
• If the glass inside the tank becomes dirty, clean it using a scraper to remove stubborn stains and then siphon the debris. Additionally, occasionally take out decorations and clean them thoroughly to remove any algae or build-up.

Buy a siphon from a pet store. You can use this tool while the fish are still in the tank, but be cautious. If you're concerned about harming the fish, you can transfer them to a separate container with dechlorinated water while you clean the tank.

Monitor your guppies for signs of illness. Guppies are relatively healthy fish, but they can sometimes develop fungal infections. One common symptom is white spots on their bodies, known as ich. White spot disease can easily be treated with medications available at pet stores.

• Keep the tank clean and well-maintained to reduce the risk of illness. If a fish dies, remove it promptly. If any fish show signs of illness, isolate them in a separate tank during treatment to prevent the spread of the disease to others.
• Some people recommend adding a bit of aquarium salt to the water to prevent fungal infections. If you plan to add other types of fish to the tank, make sure they can tolerate this environment (for example, corydoras fish do not tolerate it). Do not use sea salt or table salt in the aquarium.

• While keeping male and female guppies separately is ideal, you also need to ensure they don’t damage each other’s fins during the first few weeks. This is more common with the males.
• Guppies generally get along with most other fish, but you should avoid keeping them with fish that are prone to fin-nipping.
• Some fish might nip at guppies or refuse to share their living space, so it’s important to choose tank mates wisely.
• Since guppy fry are very small, it’s best to separate them from the parents to prevent them from being eaten. If necessary, use a fine mesh net to cover the filter intake.
• Only house guppies with peaceful fish species, as aggressive fish will nip at their fins.
• Guppies can become lonely if kept alone in a tank. To ensure a happy life, you should keep at least two together.

• Regularly monitor the pH levels of the water to ensure your fish stay healthy.
• Female guppies bought from pet stores may have already been exposed to males. They could carry male genetic material for up to a year, meaning that even a tank with only female guppies might still produce fry.