Cycling a new fish tank with high nitrites: How often to change water?

The best and safest method is through daily partial water changes, about 30-40% of total tank volume. Use only aged or conditioned water that is temperature matched to prevent stress or shock. Recommended water conditioners are AmQuel, NovAqua and StressCoat. These can be purchased online or in most pet stores or fish stores. A home test kit should be used to monitor levels. If a tank is properly cycled, beneficial bacteria will break down these toxins. Overfeeding, excessive light or heat and dead plants can cause spikes in ammonia and nitrite levels.

Hi and thanks for your request. To better control Nitrite and ammonia spikes it is best to cycle it for a month at least and measure nitrites, ammonia and nitrate constantly. Please follow the recommendations here below: The nitrogen cycle is the process of various bacteria converting harmful waste. It involves 4 steps: The first step is the decay of waste products of fish, plants, and invertebrates, along with any dead organisms or uneaten food. As these materials decay, ammonia is produced, which at even low levels will burn the gills of fish and choke off their oxygen supply. Bacteria called Nitrosomonas consume this ammonia and, in the process creating another chemical byproduct called nitrite. Although nitrite is toxic (preventing blood from carrying oxygen), fish can withstand roughly twice the amount of nitrite in their water when compared to ammonia. Next, other bacteria called Nitrobacter consume the nitrite and, in turn, release a less toxic chemical called nitrate. Nitrate requires anaerobic conditions to turn it into harmless nitrogen gas. The parameters needed to create this condition are not commonly present in most aquariums. Hence, water changes are necessary to dilute nitrate. The Nitrogen Cycle in New Aquariums Because new aquariums lack the colonies of bacteria that are necessary to provide biological filtration, the aquarium must be cycled. Cycling refers to the process of establishing and maturing the biological filter. Here's how it works: As the first fish in the new system begin to thrive, they produce ammonia. Without any Nitrosomonas colonies established to consume this toxin, levels climb and spike until the ammonia-loving bacteria population catches up. This phenomena can be observed by the naked eye as a sudden and temporary appearance of wispy, smoke-like cloudy aquarium water Ammonia levels then start to decline once the rate of ammonia production is less than the rate at which it is broken down by the bacteria. Nitrite goes through a very similar spike. Nitrite is produced through the biological activities of Nitrosomonas as they consume ammonia. As their numbers increase, so does the amount of nitrite, and in turn the population of nitrite-hungry Nitrobacter will begin booming from the abundance of nutrients. Nitrite levels will rise until the number of bacteria has increased to the point at which they break down the nitrite faster than it is being produced. The end product of this whole process is nitrate. Nitrate, in low concentrations, is not as toxic to fish and invertebrates, but can cause other problems in the aquarium. The best way to control nitrate is through regular partial water changes. Typically, new aquariums can be cycled in 2 to 6 weeks, but the actual length of time depends on many factors. Use a quality test kit to test your water conditions every other day, and when both ammonia and nitrite levels return to zero, you'll know the cycle is established.

Thanks for reaching out. Sounds like new tank syndrome, which is the time it takes for the biological filter to come up to speed, reducing ammonia to nitrites to nitrates. Continue to test and perform water changes as needed, giving the filter time to establish. Good luck.

It depends on how big the tank is as well as the type of filter in use. Smaller tanks and more heavily stocked tanks will require more frequent water changes, about 20% every week or two. Check the chemistry (ammonia, nitrites, nitrates, pH) regularly. This will give you a better idea of when to perform tank maintenance. Tetras and platys are schooling fish and ideally, do better in groups of at least 5 or six.

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.

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.

Unless you submit a water sample for culture or microscopic exam, you won't be able to determine if there are beneficial bacteria. With ammonia at the current level, there are bacterial populations. It takes time and patience to cycle a tank, sometimes up to 6-8 weeks. I'm not a fan of the "boosters", since you don't know how long they have been on the shelf or if the biologics are even active. Sprinkle some flake food in the tank and allow nature to run its course. The bacteria will feed off the flakes and populate the tank. Perform a 10-15% water change using conditioned water as needed during cycling.