Internal parasites are quite sneaky as there is no real sign of illness. If you feed live foods, it is possible for your betta to get internal parasites. Always buy food from a reputable source and follow proper storage instructions.
The only way you might be able to diagnose this problem before it is too late is to watch your betta. Take note of your betta and his daily activities. You will find they have routines and have a personality. If something changes slightly in these routines or they begin to not act like themselves, watch their weight.
Usually, but not always, your betta will be eating like normal but begin looking thinner. If your betta begins losing weight for no reason (and they do not have a lot to lose), treat your betta for internal parasites. Another common symptom of internal parasite is white and/or stringy feces.
First, do a complete water change if your betta is in a small container (25-50% water change for a larger tank if you can’t do the 100%).
The most common medication suggested for internal parasites is Maracyn-Two, as this medication can be absorbed internally.
View Healthy Betta’s Aquarium & Fish Medication Dosing Made Easy for simple 1-gallon fish tank medicine doses.
Medicated food is another common treatment method suggested for internal parasites, used in conjunction with a treatment in the tank. It should contain an anti-protozoa ingredient, such as Metronidazole. Pepso Food made by Jungle Labs is intended for internal parasites.
If your betta should die, scour and scald the tank or bowl he was in order to prevent passing the parasite on to a new fish.
Remember, do not treat your betta with medication for an illness you are not completely sure of. If you are not sure if their symptoms match a particular illness, investigate further.
Added aeration may be beneficial for your betta while treating with medication to provide them with more oxygen.
Clean water is always important for a betta but is especially beneficial for any betta facing an illness. You may find it helpful to change your betta’s water more frequently while you are treating with any medication.
Always keeping your betta warm, between 76-82 degrees F, will also help them to feel more comfortable and raise their immune system.