Who Gives A Fish Forums

We've had our Kribs for just over a week and I've noticed one of them is hiding a lot at the back of the tank. The other one seems fine, but this one is breathing really fast and looks like it's having trouble staying upright. I've caught a glimpse of it at the top of the tank, then it just floats back down - it's like it's exhausted. My OH has seen it too. Does anyone have any ideas what's going on? Is there something we can do to help it? And are our other fish at risk? We've got 4 swordtails, 5 neptunes and 6 neon tetras in there with them. We did a small water change on Saturday because the sand was getting a bit grimy, but all the water levels are okay.

I've taken a photo of the Krib that's struggling, it's just resting on the temperature gauge. I've attached it for you to see. As you can see, it's just lying there, not really doing much. I'm getting a bit worried about it, it's been like this for a while now.

To help your Krib get back on track, let's start with some basic first aid. First things first, can you please test the water for ammonia, nitrite, nitrate, and pH levels? It'd be great if you could post the results here, so we can get a better understanding of what's going on.

In the meantime, take a clean fish sponge and give the inside of the glass a good wipe down. This will help remove any biofilm that's built up, which can harbor all sorts of nasty stuff like bacteria, fungus, and protozoans.

I'd recommend doing a 75% water change and gravel cleaning the substrate every day for the next week, or until we can figure out what's causing the issue. This will help reduce the number of disease organisms in the water and give your fish a cleaner environment to recover in. Plus, it'll get rid of any gunk that's built up, making it easier for any medication to work effectively. Just make sure to use water that's free of chlorine and chloramine.

If you haven't cleaned the filter in the past two weeks, now's the time to do it. However, if your filter is less than six weeks old, it's best to leave it alone for now. When you do clean it, use a bucket of tank water to wash the filter materials, and then re-use the media. You can tip the dirty water onto your garden or lawn.

Increasing the surface turbulence and aeration will also help maximize the dissolved oxygen in the water, which should help your Krib breathe a bit easier.

It'd be great if you could post some clear pictures of the affected fish under normal white light, and also give us some more information about your tank, such as how long it's been set up, what kind of filter you're using, and how often you clean the tank, gravel, and filter. Have you added any new fish recently?

It's possible that it's a female, given what's visible of the body. Kribs typically prefer sand and caves to dig and forage in, but your tank has large gravel, which might be a problem. Without caves, she could be under stress from a male or a more aggressive female, struggling to establish a territory.

Considering you've had the Kribs for just over a week, it's also likely that you're in the quarantine period, when fish are most vulnerable to health issues due to the stress of shipping and store conditions. Many fish arrive with underlying infections, and it's not always the owner's fault. Given that you've checked your water parameters and they're fine, I'd recommend adding some hiding places with small entrances to help her feel more secure. Keep a close eye on her for any signs of infection, as this is a common issue with newly introduced fish.