How to clean a fish tank after a fish dies before adding new fish?

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.

I recommend to start with having the water tested. Many times this is offered by the pet store. If all the fish have passed away, the culprit is most often poor water quality, a disease or the tank not being properly maintained for the species of fish. I do not recommend to get more fish until you know the water conditions are correct and that you know the environment (temperature...etc) is appropriate for the species of fish you want to have. I hope this helps.

Hello, and thank you for using PetCoach. The most common (and easiest) way to clean a fish tank is with a siphon-style cleaner. Fish tanks should be cleaned in stages, generally replacing 10-15% of the water at a time. There are times where a larger cleaning might be necessary, but removing the fish and changing too much of the water at once can be quite a shock and can be dangerous to the fish, so this should be saved for only extenuating circumstances. Here's a helpful video on using a siphon cleaner: http://video.petco.com/v/18852/how-to-clean-your-aquarium-with-the-aqueon-siphon-vacuum-/ And some more reading you may find interesting on general fish tank cleaning and maintenance: http://www.firsttankguide.net/waterchange.php Hope this helps!

I would recommend to have the water completely changed. New water should be ideally submitted for quality testing. Most pet stores will do this for free or a nominal fee. High ammonia levels, PH imbalances may be responsible for that as well. Oxygen concentration and quality of the filters should be determined as well. 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.

Drop the water temperature to 80 F. Bettas do best between 78 F and 80 F. The higher temp likely did not cause her death, but warm water holds less oxygen than cooler water. She may have been ill or old. She does appear bloated in the image. It may have been dropsy or other infection. Monitor water chemistry using a liquid test kit. They are more accurate than the strips. Tou can also submit a water sample for testing. The local Petco may do this for free or for a small fee. Aim for 0 ppm ammonia and nitrites with nitrates at 20 ppm or less. Try to keep the pH as close to 7 as possible. Bettas can tolerate acidic water, but changes should be gradual to allow time for acclimation.

The frequency of water changes depends on how many fish you have in the tank with your betta, how large the tank is (i.e. how many gallons it is), how often you are feeding (more frequent feedings often results in more wasted food and more poop, so it can dirty the tank more quickly), and if you have any live plants present. The amount of salt that is needed also depends on whether you are adding salt just for maintenance or if you are treating your fish for stress or disease. My advice would be to get all of this information and contact your local pet store or aquarium store as they can then help to guide you on these specifics. Alternatively, you can gather all of this information and I can also do a consultation with you as well, whichever is easiest/most convenient for you.

As long as you are properly setting up the environment for your new fish, not stressing him out too much, and making sure he is happy and healthy, he shouldn't pass away at a certain time of day. A google search can give you a myriad of information about how to care for your betta, however most do best in an actual tank with a proper filter and heater to keep things warm and fresh, a lid to keep active bettas from jumping out and becoming injured, and for males, no other bettas or aggressive fish in the tank. If you're unsure if your tank environment is safe, most pet stores will test water samples for free and point you in the direction of any changes you need to make.