Bettas can be one of the easiest tropical fish to care for. It is this ease of care and the variety of colors and elegant finnage that has caused them to become the most popular and easily recognizable of the tropical fishes. This ease of care has caused them to become abused. Although they can tolerate small containers, they cannot tolerate dirty water. The smaller the tank, the more often it will need to be cleaned. This fact is often overlooked and remains unmentioned when one purchases a betta with a small bowl at a pet store.
When properly cared for, a betta can live a long happy life of 2-3 years with 4-5 years being not unreachable. In a laboratory setting that monitored the fish's food intake and exercise, bettas were seen to live up to 9 years! Considering this, it becomes quite sad when you hear of people complain that their betta only lived a few months in their tiny bowl or vase.
"Bettas come from puddles, they like small places."
This is a very common adage among those who have little experience fish keeping. While it is true that bettas come from rice paddies in Southeast Asia and that these bodies of water are stagnant, it is not true that these bodies of water are anywhere near small. Even a small rice paddy is acres of space. These rice paddies are highly vegetated and have very soft water. Keeping this in mind, here are some ways to create a good environment for your fish.
While some breeders do keep their bettas in containers less than a gallon, this is not recommended for the causal hobbyist. There is only a lower bound of a gallon of water for your betta. As long as there is appropriate plant cover and hiding places, he will thrive in any amount of space you wish to give him. Since there are few tank mates that are compatible with bettas, it is often best to keep them as a solitary fish. A good sized tank for this is 2-5 gallons (7.6 - 19 L). A 2 gallon tank is a very manageable size for water changes and will require a water change once a week, which is a very manageable time line for most people.
Bettas are very good at adapting to different pH levels. They can be comfortable in a range of 6.5-8.0, but would prefer 6.5-7. Many people's tap water is well within this range. It is worth getting a pH test to know where your water lies.
Since bettas are tropical fish, they require a temperature of 75-82F (24-28C). Often room temperature is not warm enough to keep them comfortable. A cold betta will be listless and often duller in color. A 25 watt heater that contains a thermostat (has the temperature on the dial instead of hi and low) will do well in a 2 - 5 gallon (7.6 - 19 L) tank. For tanks 1 - 2 gallons (3.8 - 7.6 L), there are mini 7.5 watt heaters, but these heaters only raise the temperature in the tank by a few degrees from room temperature. This means that the tank is subject to all of the fluctuation the room temperature will experience. If your room temperature fluctuates very little from day to night and from month to month, one of these mini heaters might work for you.
A betta would much rather have soft water than hard water. Hard water has also been known to dissolve finnage on some of the fancier halfmoon bettas. A natural way to soften your water would be to add mopani driftwood, blackwater extract, or Indian almond leaves(IAL, catappa leaves) in either tea or leaf varieties. These are all ways of introducing tannis into the water. Tannis is also in black tea (note: if you use this additive, make sure it is caffine free as caffine is poisonous to your fish). Adding any of these natural agents will naturally soften the water, but it will also turn the water color a weak amber color. Many people find this color attractive, but others prefer their water to be crystal clear. In this case, you will have to mix in distilled water with your tap water. Distilled water is extremely soft due to the distilling process, but do not use it pure. Your fish requires some electrolytes in the water in able to breathe properly.
Since your betta loves to have leaves to swim through and caves to hide in, your tank should provide these things. Popular easy to care for aquarium plants that your betta would enjoy include anubias, java moss, or java fern. If you are intimidated by aquarium plants, or just don't have a green thumb, silk plants are another popular option. They, and all other aquarium decor must pass the pantyhose test. Take a pair of women's pantyhose and run them over the tank ornament. If the pantyhose get snagged anywhere, that is not safe for your betta as it will snag their fins. Check every nook and cranny. If there is a visible hole in anything your betta will try and squeeze through it. They are terrible at judging whether or not they will fit. Make sure all holes are large enough to fit your betta easily or are closed off. Terra cotta pots are a very popular and cheap betta cave. Make sure the holes at the bottom are plugged or covered or drilled so that they are large enough to fit the fish.
Filtration is a highly debated topic when it comes to bettas. On one hand there are those that would never keep a fish without filtration, and on the other hand there are those who stand by attempting to emulate the low oxygen low current waters that bettas originate from, and then there are those whose beliefs are in the middle.
If you decide to filter your betta's water, make sure the current is not overwhelming. Your betta must be able to have places in the tank where he doesn't have to swim against the current. The bettas in your pet store are bred for looks and thus have long flowing tails. Carrying around these large fins is tiresome, and when there is current present, they act like sails and your fish must fight hard to remain still.
If you do not use a filter, you must change more of the water on each water change in order to keep it clean. While your betta prefers stagnant water, he does not prefer dirty water.
A happy middle ground between the two options is the use of sponge filters or air pump powered filters. When using these filters you will be able to adjust the current created by the filter by using a gang valve on the airline. There are also a few small power filters that have adjustable flow.
Often smaller tanks (1-2 gallons/ 4-8 L) are not cycled and do not have filters, while bigger tanks will be cycled. Read more about cycling here.
The amount of water you change and the frequency in which you change it will depend on a few things. First, is it a cycled tank? Secondly, do you use a filter? Thirdly, how large is the tank?
The first and second question determine the amount of water you will change, and the third will determine how often. A cycled tank with a filter should have 10-20% changed, a cycled tank without a filter should have 25-50% changed and a non cycled tank should have 100% changed. If your tank is 0.5-1 gallon, you need to perform a water change every day to every other day, 1-1.5 gallons every 2-3 days, 2-10 gallons should be changed every week, and 10+ gallons should be changed every week - two weeks.
You should always make sure you are conditioning the water before you add it to the tank. If your water smells of chlorine more than usual, you might want to add a bit more water conditioner. Water companies often add more chlorine and chloramine to the water in the summer time to prevent bacterial buildup in the pipes. Water should always be within 2 degrees of the current tank temperature to prevent temperature shock. You should also occasionally test your water to make sure that the pH and hardness are about the same. Occasionally water companies change the way they are processing the water.
As a precaution, you should acclimate your fish to the new water if you changed more than 50%.
A quick change in water temperature, pH, or other water parameters will often shock a betta. This puts great stress on a betta's system and can potentially kill them. For this reason, you should make sure that when changing your fish's water that the new water be as close in temperature as possible. To be safe, when acclimating a fish to its new water, introduce it to its new water a bit at a time.
Bettas are strict carnivores. This means they should not be fed generic tropical fish food, or goldfish flakes. Only feed your betta food made for bettas or other carnivores.
The key to a proper betta diet is variety. A mix of flakes, pellets, and live/frozen foods will help keep his digestive tract healthy and his immune system well. Good frozen/live foods are brine shrimp, bloodworms, or daphnia. Blackworms on the other hand have been loosely linked to dropsy. Be sure to soak all pelleted food in a very small amount of tank water before you feed them to your betta. Soaking in too much water will result in a loss of nutrients, and no soaking at all will potentially cause problems due to the swelling of the food inside your betta's stomach. Try to stay away from freeze dried food. This food carries little nutrients that the original product did, and can cause Swim Bladder Disorder.
A betta should be fed 2-3 times a day. Many directions say to feed as much as the betta will eat in 3 minutes. This is very poor advice as bettas do not feel hunger the same that you and I do. They will very often eat themselves to death if allowed. You should be feeding your betta until his stomach starts to round gently. It should not look like he has swallowed a marble. Do not feed your fish his next meal if his stomach has not gone down from the previous feeding.
Older bettas should be fed less than younger, more active bettas. If your betta is over 3 years old, cut back on the fatty foods such as frozen or live and feed him a bit less. Since older bettas are not as active and do not use as much energy, they also don't need as much food. Feeding too much will cause fat buildups which could kill them.