With much excitement and anticipation, you started your first fish tank. Sadly now, a few weeks later disaster has struck. Fish have died and others are looking like they would prefer to die as soon as possible. Many would-be hobbyists give up and quit at this point, break it all down and sell it all off at garage sales for a fraction of what they paid for it. Hopefully this article can help you avoid the disappointment and feeling of failure if by no other means than by assuring you that you are not alone.
Welcome to the hobby; you are experiencing New Tank Syndrome or NTS. Though obviously not a scientifically classified malady, this is a very real condition that many new fish keepers find themselves experiencing. Keep in mind that every new tank will undergo a "seasoning" process. NTS is typically the result of mistakes that have been made by an inexperienced fish keeper during this seasoning process. It is possible that the loss of fish in a brand new tank can be minimized or even totally avoided by understanding the concept of tank cycling and monitoring this process with the appropriate tests.
The root cause of NTS is almost always the addition of too many fish too soon, into an unseasoned tank. If honest, most experienced hobbyists will tell you that the exact same thing happened to their first tank. The natural human tendency is to want to get some flash and color going in our new tank as soon as possible. After all, that IS what we spent all of that money for right? Unfortunately, many times this first tank results in the death of many costly fish, a disappointed hobbyist, and quite often, disappointed parents. The good news is that there is hope. With a few simple steps you can get your tank back on the road to recovery and long-term success.
The best way to put NTS into perspective for you is to think of it as being similar to a human condition where a person with a weakened immune system will contract every disease that they come in contact with. Likewise your new fish are in such a state of stress that they will begin to contract every bug that comes along. Results can be symptoms ranging from pale listless fish who stop eating, to swollen bodies or eyes and strange looking spots and growths. You may or may not notice the appearance of reddish coloration around the gill areas or gasping for “breath”. Other fish will simply die without a single warning symptom. No doubt many of you who have reached this point, have already been to talk to someone at your local fish store. Well meaning store employees are quick to sell you expensive medicines, designed to combat each individual symptom, or even a general cure-all product to cover everything. Unless these store employees are really sharp, they will likely fail to recognize the underlying problem behind these symptoms.
Ammonia, Nitrite, and Nitrate
The majority of the time, NTS is the direct result of a heavily loaded tank that is undergoing its initial cycling process. Other lesser causes can be attributed to specific mistakes such as a failure to use a water conditioner when setting up the tank or failure to provide the proper water parameters or temperature for a certain type of fish. For the purposes of this article, we will focus on the most frequent problem of acute ammonia and nitrite poisoning. This is what is responsible for the gasping motions made by the fish as they have oxygen available but simply cannot process it into their bodies due to the effects of the poison on their gills. Depending on just how toxic the levels of ammonia and nitrites have reached, fish that survive this ordeal, will most likely have a diminished lifespan, due to the stressed and weakened immune system.
Many in-depth articles have been written on the subject of the Nitrogen Cycle that every newly established tank will go through. There is also a wealth of good information on the Internet. For that reason, I won't go into great detail here other than to give you a general outline of the process so you can understand how it affects your new tank. One thing to remember is that this is not an optional process. It is going to happen within your tank, whether you like it or not so the best thing you can do to ensure success is to understand why it happens.
It all starts with the fact that fish excrete a chemical called ammonia. Fish waste and waste food also create ammonia. In the wild it is not a problem because the water is constantly circulated and ammonia does not accumulate. In the tank however it will accumulate and must be dealt with. Luckily for us, there are millions of tiny bacteria that will “eat” this ammonia. These bacteria are already present on surfaces and in water but in small quantities. When a steady source of ammonia such as a fish is put into a tank of water, the colony of bacteria begins to grow and will eventually cover all inside surfaces of the tank, gravel, decorations, and most importantly the filter media. This colony of bacteria will grow proportionately to the amount of ammonia that they are being fed and will reach the level where they have the capacity to process all new ammonia as it is introduced into the water by your fish. In reality the ammonia is not disappearing, but instead it is being converted into another chemical called nitrites.
When ammonia gives way to nitrites in your tank, this is where things really start to become very toxic for your fish. Nitrite actually seems to be more harmful than ammonia, partly due to the “double-whammy” effect of having ammonia first, followed by nitrites. This is typically the stage where fish exhibiting symptoms of illness, and/or begin to die. Luckily for us again there is another group of bacteria that will grow and “eat” the harmful nitrites.
The Cycling Timeline
When we start up a new tank from scratch, we can expect to see a build-up of ammonia first (typically in about the second or third week) followed by a build-up of nitrites while the level of ammonia is dropping to zero. Eventually both ammonia and nitrites will drop to zero and we will see the buildup of yet another chemical called nitrate. Nitrate is much less toxic than ammonia and nitrite, and is easily controlled with a regular water change maintenance routine. The entire process can be expected to last for approximately 4-6 weeks. How to tell for sure if your tank is still cycling? If either your ammonia or nitrites show a positive reading, your tank is still cycling. A healthy established tank should never have a positive reading for either of these two chemicals. Your local fish store should be happy to test your water for these chemicals upon your request. It is in their best interest to test for you and most will require it as part of the guarantee offered on their fish.
Getting the tank under control
OK, now that you understand the root cause of the problem, what to do? First of all, keep in mind that your remaining fish have been through a very rough experience. What you DON'T want to do is make things even more difficult on them by adding various medicines or chemicals unless you can see and diagnose a clearly defined disease. If you have already added medicines, then sometimes the best thing you can do for your remaining “healthy” fish is to discontinue the meds, do a major water change, then place fresh activated carbon in your filter. At this point you will need to evaluate the remaining fish in the tank. Any visibly sick fish need to be removed from the tank, and either quarantined in a “hospital” tank, or euthanized as humanely as possible. Please do not ever flush a live fish down your toilet. One method of euthanizing a very sick fish is to wrap it in a paper towel and place it in your freezer.
Now look at your remaining “healthy” fish and evaluate whether or not you are still overstocked and should consider taking some of them back to the store. If your tank was completely out of control and all or most of the fish were lost, consider scrubbing it out and starting over using the Fishless Cycling method. This method employs the physical addition of pure ammonia in a controlled manner that replicates the ammonia generation levels of a large load of fish, but without risking the health of any fish.
Going forward again
OK, you seem to have stabilized the tank through quarantine, water changes, and carbon. Now what? Assuming that you haven't started over using the fishless cycling method, you now need to help your remaining fish through the rest of the cycling process. This involves actively intervening to prevent ammonia and nitrites from reaching toxic levels again. The best way to accomplish this, is with a program of frequent water changes. Monitor your water with ammonia and nitrite test kits, and don't be afraid to change water every single day if necessary to ease your fish’s suffering. Keep in mind that this very process of changing water, has the potential to prolong or delay the completion of your cycle but this is what it takes to keep the rest of your fish alive and reasonably stress free.
While changing all of this water, it is also very important to use a water conditioner that specifically neutralizes chlorine and chloramines. These are chemicals, which are likely to be present in your tap water and are quite harmful to fish. Also at this point of starting over, this would be a great time for you to visit your local fish store and obtain some “seeding” material, in the form of a bag of gravel, or filter media from one of their established tanks. This will be loaded with beneficial bacteria and will help jumpstart your cycling process.
For the next few weeks, continue to make your frequent water changes and watch your fish for signs of distress such as redness around the gills or gasping for air etc. If possible, set up a separate hospital tank in the event that you experience another outbreak of diseases that you have seen before or new ones. The two most important things you can do during this period are to not add any more fish to the tank and don't feed your existing fish very much. If you are using standard flake food, cut way back to a few flakes, once a day until you get out of trouble. After a few weeks it might start look tempting to start stocking again because things seem to be under control but it wouldn't take much at this point to start another ammonia spike. When things do stabilize and you see readings of zero ammonia and zero nitrite for a period of several weeks after the last positive nitrite reading, it is probably safe to assume that your cycle is completed and it should be ok to add fish again *SLOWLY*. Beware of adding too much fish and overloading your newly formed bacteria colonies. This can quickly turn the situation toxic again. Depending on the size of your tank of course, one or two fish added per week until fully stocked is the kind of pace that you will want to maintain. As for your surviving fish, it is important to remember that this ordeal that they have been though can have lasting effects for some time after the last traces of ammonia and nitrites have left your tank. If some of these fish continue to die, you need to resist the urge to start medicating the tank again but instead take a serious look to see if the fish that are having the problem now were among the ones most affected by the NTS. Above all, be patient and remember that once your initial troubles are behind you, it is important to maintain a regular water change maintenance routine for the continued health of your fish.
I hope that this has been of some help to you. Few things are more rewarding for a new fish keeper, than to end up with a healthy and happy tank, where fish are thriving and displaying the instincts that they were endowed with. For most of us, this success usually results in the desire to create another tank as soon as possible. Now that you know how to avoid the pitfalls that created havoc with your first tank, take the time to do things the right way. Either fishless cycle the tank, or add fish VERY slowly over an extended period of time. The results will be a tank you can be proud of.
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