Q: KW wrote,

Your website and blog are very useful to a first time betta owner, but I am having trouble deciding whether or not my betta is sick. I bough two bettas five days ago and have noticed some changes. When I first got them, Redfish was very active, swimming around a lot and flaring at himself. Bluefish, on the other hand, kept his fins tightly pulled in and sat around on the bottom.

Three days later, however, they seem to have reversed places. Bluefish is active and shows interest in my fingers and comes up every time I lift the lid. He also really enjoys eating. Redfish has now become sluggish and tends to sit on the bottom, where every now and then he will swim up for air. He also refuses to eat flakes. He is now moving around so little that I am getting worried.

I’m pretty sure it’s not the water, since they are in a divided tank, and Bluefish is doing fine. Is it normal for bettas to become almost lazy for a while? Could this only be a temporary thing, or should I do something, and what?

A:Thanks for writing in. At this time I wouldn’t worry too much about Redfish or Bluefish acting a little out of sorts. The first two weeks in a new aquarium are quite stressful as the water conditions can be quite different from what they were in previously. The pH may be different, the general hardness, even going from a dirty tank to to a clean one can cause added stress. It’s not unusual for Bettas to stop eating or become a little lethargic. During these early days, Bettas frequently experience stress that can lead to disease.

The best thing you can do is provide a clean, warm and stable environment for your bettas and continue to observe them for any common signs of illness. In addition to sluggishness and appetite loss look for bloating, fuzzy white or gray patches on the body or fins, stringy fibers, fin loss or fin rot, redness under the scales, protruding scales or eyes, open wounds, swollen gills, quickened breathing, tiny white salt like spots on the body, fine rusty dust looking spots or rapid darting, etc. All these can be signs that the stress has evolved into an illness. At that time you could treat appropriately.

As for feeding, I recommend a variety of foods to ensure a balanced diet. A lot of bettas won’t eat flakes at all because they seem to be less appealing and often they have never seen them before. Breeders generally feed them live and frozen foods so finickiness over flakes is pretty common even in healthy bettas. You could also try pellets, freeze dried bloodworms or brineshrimp, or even try the frozen varieties as they have become quite common even at the large chain stores like PetCo and PetsMart. Bettas also tend to find them to be more delicious.

As you observe your bettas daily, continue to keep their water clean and free of any ammonia or nitrite. To encourage good health and activity, keep the water warm and stable with an aquarium heater set to about 78*F to 80*F or so.

I also recommend using a lot of aquarium plants or an opaque tank divider so the fish can’t see each other all the time. They are territorial by nature and being in constant view of an intruding male can lead to unnatural stress. This is especially important if one or both fish aren’t in great health.

If anything changes or if either one’s health worsens let me know and we can go through each water parameter and see if anything is out of the norm.

Post Rating
1 Star2 Stars3 Stars4 Stars5 Stars (1 votes, average: 5.00 out of 5)

Reader Interactions


  1. Anonymous says:

    Just to update – both Redfish and Bluefish have cheered up and become more active. They have also produced nice bubble nests, so it must have just been adjusting to the new tank that made them unhappy.
    Thanks. KW

  2. Cana Cook says:

    Hi. I have two bettas who I adore and they are kept in seperate tanks in my room. They are on opposite sides of the room, but yesterday I noticed that one of them was flaring a lot. He has been acting strangely lately and I’m really worried. I got him about a month ago and he seemed fine until about 4 o’clock last night. I noticed that he seemed to be attempting to shove himself under the large rocks in his tank, which I have since removed. He hasn’t been eating and he just sits at the bottom of the tank most of the time. He seems to be avoiding the middle of the tank for some reason and he won’t eat, and I’ve tried both flakes and pellets, but he just ignore’s them. I changed his water yesterday and when I put him back into the tank he perked up a bit, but not much. Also, last night I noticed some strange white speck like balls on him. I’m worried he might be sick. Please help!

Leave a Reply

Your email address will not be published. Required fields are marked *