How long has she been breathing heavily like that?
Do a 75% water change every day for a couple of weeks and add some salt.
Make sure any buckets/ containers you use are free of chemicals and haven't been used for any cleaning products. Likewise, make sure you don't have any cream, soap, grease, hand sanitiser or anything else on your hands.
Make sure there are no fumes, aerosol sprays, cigarette smoke or anything else in the air that could poison the fish.
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SALT
You can add rock salt (often sold as aquarium salt), sea salt or swimming pool salt to the aquarium at the dose rate of 1 heaped tablespoon per 20 litres of water. If there is no improvement after 48 hours you can double that dose rate so there is 2 heaped tablespoons of salt per 20 litres.
If you only have livebearers (guppies, platies, swordtails, mollies), goldfish or rainbowfish in the tank you can double that dose rate, so you would add 2 heaped tablespoons per 20 litres and if there is no improvement after 48 hours, then increase it so there is a total of 4 heaped tablespoons of salt per 20 litres.
Keep the salt level like this for at least 2 weeks but no longer than 4 weeks otherwise kidney damage can occur. Kidney damage is more likely to occur in fish from soft water (tetras, Corydoras, angelfish, gouramis, loaches) that are exposed to high levels of salt for an extended period of time, and is not an issue with livebearers, rainbowfish or other salt tolerant species.
The salt will not affect the beneficial filter bacteria but the higher dose rate (4 heaped tablespoons per 20 litres) will affect some plants and some snails. The lower dose rate (1-2 heaped tablespoons per 20 litres) will not affect fish, plants, shrimp or snails.
After you use salt and the fish have recovered, you do a 10% water change each day for a week using only fresh water that has been dechlorinated. Then do a 20% water change each day for a week. Then you can do bigger water changes after that. This dilutes the salt out of the tank slowly so it doesn't harm the fish.
If you do water changes while using salt, you need to treat the new water with salt before adding it to the tank. This will keep the salt level stable in the tank and minimise stress on the fish.
the only time that female breathes that much is when she isolates herself. I normally do 2 40-50% water changes a week as it is still a fairly new tank, and clean the gravel every time I do that. the video shows the opposite side of the tank to the filter and I'm pretty sure there is enough surface turbulence. however ill still make it a bit more choppy and clean it out a bit more for a week, just in case.
