Why Does the Water Turn Yellow in a Fish Aquarium?

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A fish tank turning yellow might seem like something out of a horror movie, but this situation isn't as scary as it may seem. When fish tank water looks yellow, it's very often a sign that something's amiss with the water quality, filtration, or cleanliness of your pet's aquarium. In fact, bad aquarium water is the number one reason these pets fail to thrive. Keep your pet fish happy by watching his environment closely so you'll notice a fish tank turning yellow. This includes careful feeding, quality filtration, testing the water for various substances, and using the right kind of greenery in the tank.


When the water in your aquarium begins changing colors, it is often a signal that attention is needed.

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Fish tank turning yellow

Water quality is extremely important to a fish's survival as a home pet, so make a point of getting a liquid test kit (not the strip version) and use it to assess the environment you plan for your fish. Depending on the type of fish you own, you should check for the correct levels of ammonia, nitrites, and nitrates as well as the water's pH level, alkalinity, and hardness. With properly monitored and balanced H2O, fish tank water that looks yellow won't be a problem.


Feed fish carefully

When fish tank water looks yellow, it could be because you're too heavy handed with fish flakes or your kids are being too generous with the pellets at meal time. Overfeeding fish can lead to cloudy, dirty water, and it can increase the amount of certain substances in it to dangerous or even toxic levels. As a rule, don't offer more food than your fish can consume in about 30 seconds. When it comes to fish food storage, don't keep anything longer than six months. Shop for fresh fish food often and be sure to store it in a cool, dark place.


Best filter to keep a fish tank clean

Keeping a fish in a bowl without a filter could leave you with a fish tank turning yellow. The reason? Without good filtration, your pet's water can end up becoming a noxious stew of chemicals and pieces of waste. Your best bet is to seek out the best filter to keep your fish tank clean. If you can, choose filters that have a quiet hum. If these devices make loud noises, the din can get in the way of your fish's ability to communicate at her preferred low level of frequency.


Fake vs. real plants

Fake plants offer beauty and places for your fish friend to retreat when he's had a long day of toddlers banging on his glass. Real plants can serve the same purpose, but eventually, they'll break down inside the tank and add to the problem of your fish tank turning yellow. It's better to stick with faux greenery for this reason along with other decor so your fish can entertain himself and hide out when he needs a break. Some fish even enjoy crafting a nest from rocks that many people use to line the tank's bottom.


Call your fish's vet

If you've battled to clean up your aquarium and still find that your fish tank water looks yellow, you may need to check in with your pet's vet. Less than clean water can lead to a sick fish, but an appointment with a piscine pro can help you determine whether the water is at fault or if something else is bothering your fish. Fish can actually be prescribed medications and can undergo surgery if necessary. Keep in mind that over-the-counter remedies aren't considered ideal when it comes to treating fish sickness. Instead, it's better to call an expert.