My fish tank water is cloudy and green. How do I make it clear again?
Updated On September 23rd, 2025
Pet's info: Fish | Unknown - Fish | Female
Our tank has turned cloudy and green.. What will help this.
2 Answers
Most Helpful Answer
Published on October 30th, 2017
Weekly to biweekly 25 % water change can keep the water healthy. Also, monitor the temperature and water chemistry and adjust as needed. You many consider wiping down the sides often to prevent algae from Growing on the glass. Best of luck and thank you for using Pet Coach.
1Pet Parents found this answer helpful
Related Answers from Veterinarians
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Published on July 25th, 2018
Water gets cloudy if you overfeed your fish, if your tank is overstocked and if your filter system is not working properly. Replace 1/3 to 1/2 of the water in the tank Remove any excess dirt and mulch from the bottom of the tank, do not feed your fish for 2 or three days and when you feed them again feed only as much as they will eat in one minute. If any food sinks to the floor, you are feeding too much. Clean your filter , and if you do not have one, get one suitable for the size of your aquarium.
2Pet Parents found this answer helpful
Health & Wellbeing
Why is my water cloudy
Water gets cloudy if you overfeed your fish, if your tank is overstocked and if your filter system is not working properly. Replace 1/3 to 1/2 of the water in the tank Remove any excess dirt and mulch from the bottom of the tank, do not feed your fish for 2 or three days and when you feed them again feed only as much as they will eat in one minute. If any food sinks to the floor, you are feeding too much. Clean your filter , and if you do not have one, get one suitable for the size of your aquarium.
Updated on September 24th, 2025
Health & Wellbeing
Why does my water turn green after 2-3 weeks? No live plants and 1 artificial log in the tank!
The green you see is algae. These like nutrition-rich water and lots of light. So you are probably feeding your fish too much and they are not eating all the food. Also there may be too much day light reaching the tank. I suggest you cover your tank in such a way that most of the day light is removed. Fed your fish sparsely. That means, only feed what they can and will eat within one minute. Get some algae-eating fish like a small pleco. Also change about 1/3 to 1/2 of your tank water to remove some of the algae floating in the water.
Updated on September 24th, 2025
Health & Wellbeing
We have a Betta baby girl fish. We have the Marina Betta EZ Care tank. We added more water to clean it (instructions say so) and now the water is cloudy and merky. Did we do something wrong?
This can happen when a tank is not properly cycled or if too much water is changed/added. Check water chemistry using a home test kit or by submitting a water sample for testing. Most pet stores will do this for free or for a small fee. Aim for 0 ppm ammonia and nitrites and 20 ppm or less nitrates. You will likely need to do partial water changes to keep ammonia levels in check until the tank clears up. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Bettas do best between 78 F and 80 F. Brands for water conditioners include AmQuel Plus, NovAqua, Prime, StressCoat or StressZyme. These can be found in the aquarium section of the local Petco.
Updated on September 24th, 2025
Health & Wellbeing
We have four cardinal tetras, three glo danios, three glo tetras and a albino Cory cat. They are all the type to only get an inch to two inches long and so we have them in a twenty gallon tank. Have gravel and silk/plastic/resin/and live plant/decor
Too much light can cause algae growth which will give a murky or cloudy appearance to a tank. Use a timer and set it for a 12hr on/off light cycle. Move the tank away from direct sunlight if necessary.
Perform a 20-25% water change every week. Use aged or conditioned water that is temperature matched to prevent stress or shock. Rinse filter media with tank water to preserve bacterial population. Use a test kit to monitor water quality. Ammonia spikes can lead to algae blooms. Ammonia and nitrites should be 0.25ppm or less, nitrates 30ppm or less. If the tank is not "mature" or fully cycled, the excess wastes from fish can feed algae or bacterial overgrowth.
It may also be diatoms which are harmless and can appear a few months after a tank had cycled. They'll resolve on their own in a month or two. Keep on top of cleaning and water quality.
Updated on September 24th, 2025
Health & Wellbeing
My blood parrot cichlid's tank is extremely cloudy. Whenever I clean his tank I usually put in some water clarifier and conditioner in, and normally this works just fine and the water is clear. However, I recently just got a 30-gallon tank. When addi
This can be due to micro bubbles from the filter. This will typically resolve in a few days. If the filter outflow creates a large amount of turbulence, try decreasing the flow rate. Another cause can be a bacterial bloom. This is a common occurrence after a water change and is caused by elevated ammonia levels or large amounts of organic matter in the tank. Either can feed bacteria and promote overgrowth. Check the filter media and rinse it, with tank water not tap water, if necessary. Check the water chemistry using a home test kit or by submitting a water sample for testing. The local Petco may do this for free or for a small fee. Ammonia levels, ideally, should be 0 ppm. Perform a partial water change if necessary. Use only conditioned water that is temperature matched to prevent stress or shock. Condition the water before pouring it into the tank. Remove any dead or dying plants, limit lighting, monitor water temp and don't overfeed. This will decrease the chance of a bloom occu
Updated on September 24th, 2025
Health & Wellbeing
Why is my fish tank cloudy? How can I clear it up? I put some chemical in it but it didn't seem too effective. (Sorry my phones camera is really bad)
Thanks for reaching out. You need to determine why it is cloudy before you can treat. Test for pH, ammonia, nitrites and nitrates. Exam the filters and clean if necessary. Some fish stores will let you bring in water samples to test. Good luck.
Updated on September 24th, 2025
Health & Wellbeing
I clean my fish tank because it got really cloudy I put in all the drops that are supposed to. Woke up the next morning and three of my fish were dead. So I clean my water again and put the remaining fish back in it. But my fish tank is cloudy once a
This cloudiness is likely due to a bacterial bloom. This can happen if a tank is not properly cycled. Changing the water may make the condition worse. The fish could have been killed by elevated ammonia or nitrite levels. Use a home test kit or submit a water sample for testing. Most pet or fish stores will do this for free or for a nominal fee. If it is a new tank, allow it to properly cycle. This can take 4 or more weeks for the beneficial bacteria to populate the tank and filter. Once ammonia and nitrites are at 0.25 ppm (parts per million) or less and nitrates are at 40ppm or less, you can add fish. Goldfish are cold water fish and do best between 65 F and 72 F. They also need a larger aquarium than most fish. 20 gallons per fish plus an additional 10 gallons for each additional fish is recommended. They produce a larger than normal bio load which can quickly foul water, so a filter rated for at least twice the tank volume is strongly recommended as well.
Updated on September 24th, 2025
Health & Wellbeing
Really Need your help! Our turtle tank is all cloudy. Changed water put alges a Really NEED YOUR help. Our turtle Aquarian is all cloudy. Can see the turtle even. Changed water and put in alges cleaner. But this is the 2nd time this has happene
The cloudiness can be due to elevated ammonia or nitrite levels or algae blooms. If the tank was previously cycled, the water change may have disrupted the nitrogen cycle resulting in cloudy water.
Check the water temperature and chemistry. It is okay to cycle a tank with a turtle in it. They are hardier than fish and can withstand the elevated ammonia and nitrites until the tank chemistry "settles" down.
Updated on September 24th, 2025
Health & Wellbeing
Hi i have a Small fish Tank 1.6 gallon i originally got it for 2 fish a small gold fish and a terra a neighbor gave us 2 more gold fish the water of the tank went real cloudy and has an odor as this is the first time we have fish I'm probably doing s
These signs are quite concerning and should be approached radically. Begin by submitting a water sample for quality testing. Most pet stores will do this for free or a nominal fee. Clinical examination should always include a water quality check, even if you have done so already. Water testing should be performed with a quality test kit, measuring NH4, NO2 and NO3. High ammonia levels, PH imbalances may be responsible for these signs. Oxygen concentration and quality of the filters should be determined as well. If water quality is good and there are no major imbalances, your fish should get examined to look for any sign of bacterial/fungal infection and eventually water should be treated. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further.
Updated on September 24th, 2025
Health & Wellbeing
hi, I need some help with water condition of my fish tank. I’ve recently got 6 new fish and added in my 10 gallon fish tank three days ago. I did set up my tank for 48 hours before adding fish but now the water gets cloudy with tiny air bubbles on th
48 hours is not long enough for a tank to properly cycle. Several weeks to a couple months are needed for beneficial bacteria to populate the substrate and filter. These bacteria break down wastes (ammonia, nitrites, nitrates) that are harmful to fish and can promote bacterial blooms resulting in cloudy water. The overfeeding likely contributed to the bacterial bloom. You can cycle with or without fish, however cycling with fish will increase the risk of loss. You'll need to monitor chemistry using a liquid test kit. The kits with strips are not as accurate. Perform partial water changes, no more than 25%, every few days or if ammonia levels begin to affect fish. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Feed them every other day. Normally, you would add one fish at a time but that isn't possible for you now. Monitor chemistry and perform water changes until ammonia and nitrites are 0.25ppm or less and nitrates are 40ppm or less. This
Updated on September 24th, 2025
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