Why do fish hide? You may not see your fish for a long time after that initial drop in the tank. It could be for many reasons, such as their temperament or sensitivity to light. They could also be guarding fry or feeling vulnerable for other reasons. But one of the most notable reasons fish hides is because they’re dealing with stress. You’ll find more information below to help you understand why your fish may be hiding and what you can do about it.
One reason your fish may be hiding is their temperament. A fish’s temperament isn’t going to change. So keep this in mind when researching what type of fish to bring home. Unless you keep a bare tank – which we don’t recommend – you’re not likely to see a shy fish very much at all. One thing you can do to help your shy fish feel more comfortable is to pair them with a carefree tank buddy to show them the environment is safe. Dither fish bring timid fish out of hiding by actively swimming around, letting others know that danger isn’t close by.
Another reason you might not be seeing your fish is that your timelines aren’t matching up. Some fish are less active when there’s a lot of light. So when you're awake, they're in hiding, and when you're asleep, they're swimming about. You’re more likely to see this type of fish at night or when it’s dark. If you're worried about your fish, check on them at various times to see if light exposure may be discouraging them from being out and about.
If your tank contains both males and females, your fish could be hiding because they’re guarding eggs or juvenile fish. When fish guard eggs or fry they’re going to feel extra vulnerable and try to stay out of sight. Some fish hold their offspring in their mouth, making them unable to fight back if another fish becomes aggressive. To provide safety for themselves and their spawn, they’ll find a safe place to hide or stay out of the way. You might see them tucked behind an aquatic plant, crafted rock hideout, or sponge filter.
After ruling out temperament, sensitivity to light, and the possibility of offspring, you need to consider stress as a reason your fish may be staying out of sight. Stress shows itself in a variety of ways, and there could be several causes of stress in your tank. The most apparent stressor is bullying from a more aggressive fish. Take note of any fish that are pushing others under a pile of rocks, into a corner, or behind a filter. If that's the case, form a backup plan with your exotic pet vet to keep your tank a happy place. Another stressor is illness. If you notice your fish is a little more standoffish than usual, look for signs of disease. Your fish, like humans, may prefer to be on their own if they’re injured or unwell. Keep a close eye on your fish if you suspect they’re sick or injured. Reach out to a veterinarian or experienced fish keeper if they don’t seem to be improving. You may need to quarantine the fish or treat the entire tank. Identifying the reason your fish is hiding will give you valuable insight and understanding of their needs and help you worry less about the health of your pet.
