https://www.chewy.com/education/fish/general/why-is-my-fish-tank-cloudy
Cloudy aquarium water is a common issue that signals an imbalance in your tank’s ecosystem, though it is not always immediately harmful to your fish.
Common causes include bacterial blooms in new tanks, overfeeding, excess light exposure, unwashed substrate, and overcleaning - which can strip away essential beneficial bacteria.
Medications, particularly unregulated antibiotics, can also disrupt the biological balance. Each of these factors can contribute to murky water, and in some cases, they may lead to ammonia buildup - a toxic substance that can stress or harm your fish.
Signs of ammonia related issues include lethargy, gasping at the surface, and changes in gill color.
To address cloudy water, first test your ammonia levels and check your tank’s temperature.
Avoid drastic measures like replacing all the water or scrubbing everything clean - doing so can worsen the problem.
Instead, perform gradual water changes (10 to 50%), make sure new water is properly conditioned, and reduce direct light exposure to prevent algae blooms.
Let your tank's bacteria naturally rebalance, unless ammonia is present, in which case immediate action is needed.
To prevent future cloudiness, avoid overfeeding, rinse new gravel before use, maintain a proper light cycle, and follow a consistent but gentle cleaning routine.
Chewy editorial team breaks down the most common causes, along with effective treatment options and prevention tips - so you and your fish can get back to enjoying a clear, healthy tank.
