Fin rot and fin nipping are two of the most commonly mistaken issues with keeping bettas, and often leads to incorrect methods of solving the issue, and in some cases, lead to extreme methods of treatment to solve an issue that might not even exist.
Fin rot and fin nipping look very similar, however fish showing signs of fin rot will usually present some indication of infection, such as reddening or blackening (can also just be as a result of healing and pigment change) around the deteriorated areas.
In most cases of fin rot, the cause is either ruled down to poor water quality, infection occurring after nipping, parasites, or stress (lowers the immune system).
If the fins are looking a bit shabby, it is important to never jump straight into treating. The first step should be to evaluate the situation:
- Is the tank an appropriate size? Generally, 5 gallons or 20L is the minimum tank size, and should be filtered and fully cycled.
- Are the parameters normal? Ammonia and nitrite at 0ppm, and nitrate no higher than 20ppm.
- Is the filter too strong and causing a current?
- Is the tank warm enough? Optimum 26C (80F)
- Is the temperature fluctuating by 5 degrees or more?
- Is there any reflection causing the betta to flare and become stressed?
- Any other stress-causing factor such as lack of plants, tank mates, etc?
- Check over your methods for doing water changes.
Usually, fin rot can be solved by just improving water quality or taking out one of the above factors that is causing stress. Any form of stress to any animal will weaken the immune system, leaving fish susceptible to ailments such as fin rot.
Before beginning treatments such as rock salt, it is best to try and reduce stress as much as possible. This can be done by keeping the tank well planted, making sure the water conditions are correct and the tank size is also correct or even improving diet.
Fin nipping should always be considered before starting treatments. Nipping is quite common and often hard to stop, however the most common causes of nipping are stress, boredom, poor diet, weight and length of fins, and incorrect housing/water conditions. Nipping often happens at night and can be a little difficult to catch, and damage is usually done within a minute. Here are some common types of nipping seen in bettas. It is a myth that only bettas with long fins can nip, as bettas having shorter fins are just as capable at turning around and damaging their fins. It is just much more common for bettas with longer fins to nip.
It is very common, especially for new nippers, to develop fin rot the first few months they begin nipping, which can make it extremely difficult to identify the cause of infection.
Reasons such as fin nipping is why harsh medications should never be used when first noticing suspected fin rot, as medications can actually aggravate fin nipping issues. Medications themselves also put stress on fish and will lower the immune system, so it is best to begin with the simplest of treatment methods first.
When first suspecting fin rot, water changes should be the first course of treatment after checking water parameters, temperature, tank size, and stress-causing factors, and should be around 30-50%. Just like all other water changes, it is very important to match the pH and temperature of the new water. Not doing so can cause stress and may also be a reason for the onset of fin rot or fin nipping. Generally, water changes of 30-50% every second day is plenty.
If no improvement is seen within a few days, then rock salt (no additives) may be added to the tank at the dosage rate of 1 tsp per 5 gallons of water. This is a very low dosage and is often all that is needed alongside water changes for small cases of fin rot. If it seems more severe, or you want to increase that dosage, you can dose up to 0.05% (1 tsp per 2 gallons of water).
Salt should always be added progressively, as bettas can sometimes have intolerance issues to salt where they cannot properly balance the salinity levels within their bodies when salt is added. This can cause flashing, colour loss, progressive and rapid fin loss, nipping, pine coning, as well as irritability. Generally, the salt levels should be kept no higher than 0.1%, however some issues may require a higher dose which can be increased with moderation.
If salt (generally a dosage of 0.05%) and water changes every 2-3 days for two weeks does not result in any improvement, fin nipping should be ruled in as a likely cause, and other methods of reducing stress should be considered.
For stressed bettas, a well planted tank will often help provide a sense of protection. All territorial fish need a sense of security and a place to hide out of sight, and this will often help reduce stress and allow the fish to rest.
If flaring is the cause, look into increasing the light outside of the tank as well as inside the tank to reduce reflection. Planting around the glass will also aid in preventing reflection as well as adding a white background.
For bored bettas, adding things such as tank mates (shrimp and snails) will allow them to watch and be entertained, which should help reduce boredom. Socialising more often or putting the tank in a social area will also aid in preventing boredom, and you can always add a small ping pong ball to the tank which the betta will flare at and play with.
For undernourished bettas, diet should be improved. Poor diet can often result in fin loss caused by a lack of nutrients within the fins. Protein should be a main part within their diets and should be varied.
Occasionally, bettas such as halfmoons may nip due to the length or weight of their fins. This is generally because the tank is too deep, or the filter is too strong, however it can just occur because the betta wants his fins to be a certain length/weight.
In all cases of nipping, it is important to keep the water as clean as possible to prevent infection.
Medications: Medications are often not needed in cases of fin rot and can cause more stress than needed. It is always best to begin with the simplest of methods first, which also reduces the chances of antibiotic resistance which can result in cases such as chronic fin rot. If medications other than aquarium salt are to be used, make sure to research them to find out if they are suitable, and always dose to the correct amount and complete the entire duration of treatment.