My tank is cloudy and fish died. When can I add an Oscar?

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 occurring due to excess organic matter. Luckily, bacterial blooms are not harmful to fish. They can be frustrating, but they do clear up eventually.

I would recommend checking your water quality first to evaluate your ammonia, nitrite, and nitrate levels. With new aquarium set ups, it is common to have issues with water quality as your bacterial populations are getting established. I am not sure if you have fish in your tank already or not, but if you do, please monitor them closely for signs of distress, as this can occur with elevated ammonia and nitrites. Signs to look for would be swimming very fast (hyperexcited state) and trying to jump out of the tank. I hope that gives you a place to start, and good luck!

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.

These are quite concerning but generic signs. The approach must be logic but quite radical at the same time. 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.

It is possible the tank has not cycled properly which results in high ammonia and nitrite levels which can kill fish. Allow the tank to run, without fish, for at least 4-6 weeks. During this time, use a home test kit or submit a water sample for testing every few days. The local Petco may do this for free or for a small fee. What you are looking for is to have ammonia and nitrites at 0 ppm and nitrates at 20ppm or less. pH can hover around 7 for most community fish. Avoid large, rapid swings in pH though. What is happening in the tank during this time is that beneficial bacteria are populating the gravel/substrate and the filter. These bacterial populations are responsible for the Nitrogen Cycle. This cycle breaks down wastes from fish, uneaten food and plant matter into by-products that are filtered out or dissipate. You can "cycle" a tank with fish, however this increases the risk of loss. Once your tank has cycled, you can add fish. You will still need to monitor water chemistry and perform partial water changes regularly. Use only conditioned water that is temperature matched to prevent stress or shock. You will also need to vacuum the gravel regularly and rinse the filter media. Never use tap water to rinse. Use a bit of tank water to protect bacterial populations in the sponge.

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.

I am sorry for the loss of your fish. Bettas are quite hardy, but cycling the tank would be recommended if you are starting fresh. The moss ball and snail can be placed back in the tank once it is set up. Cycling may take 3-4 weeks ina small tank. Monitor the chemistry closely. Once ammonia and nitrites are at 0 ppm and nitrates are 20 ppm or less, you can introduce fish. Cloudy eye is typically due to injury, poor water quality, stress or a combination of the three.