New Tank Syndrome

So, you've got your new tank set up. You followed everyone's advice and bought as large a tank as your budget - and space - allowed. You've got a new "Super Eagle Model 5" filter, which was highly recommended as being the best on the market. You added attractive gravel and ornaments, a good quality heater, and an accurate thermometer. You filled the tank with water, and were careful to use a dechlorinating additive, as everyone at the fish store recommended. You've allowed the water to sit for a couple of days, and have adjusted the heater to maintain the water at the desired temperature for your fish. Next, you bought some very healthy looking fish, and carefully floated the bag in the water for 15 minutes, to equalize temperatures. You slowly added tank water to the bag, and after another 20 minutes you added the fish to your aquarium. Everything looks great. The fish have quickly adjusted to their new home, and are swimming around and exploring. All looks well, and you are proud that you have done everything right to reach this successful conclusion.

Well, not quite. 3 or 4 days later, you notice your fish are having difficulty breathing, and appear listless. Worse, there is something wrong with your filter - it's not keeping the water as clear as it was in the beginning. The water is beginning to turn milky white, and - horrors - you notice one of your new fish has died! Something terrible is happening in your tank, but you don't know what. What could possibly have gone wrong?

Welcome to the frustrating world of New Tank Syndrome.
To understand what is happening to your beautiful new tank, you need to understand what changes occur in a new tank. All new tanks start out "sterile." That is, they have no bacteria, no organic life forms, just clean rocks and ornaments and filter. Fish, meanwhile, are doing what fish do best: eating and pooping. The waste product of fish is very high in ammonia. This ammonia has nowhere to go (you can't "flush" an aquarium), and so it builds up in the water. Eventually, after a few days, the ammonia level builds to the point that it becomes toxic to fish. (Imagine how your health would suffer if you had to live in your unflushed toilet for a few days. Not a pretty thought!)

Why, then, do fish not have this problem in nature? Why does your neighbor's tank, which he has had running for 8 months now, look so beautiful, while yours is not doing well at all? And why is his water clear, while yours is turning cloudy white? Most important of all, why doesn't your expensive new filter remove this white cloud? Did you not buy the filter the nice salesman recommended? Didn't he tell you that this filter would easily handle the fish in your tank?

Well, he didn't lie. The filter is more than capable of handling the fish load in your tank. What he didn't tell you is that before this can happen, the tank must grow a colony of beneficial bacteria. These bacteria are the secret of why a tank can run day after day with the water remaining clean and clear and healthy. Ammonia is removed from the water by bacteria commonly referred to as Nitrosomonas. These bacteria "eat" the ammonia, and remove it from the water. However, being life forms themselves, the bacteria convert the ammonia to another form of chemical called nitrites (notice the spelling, "ites" on the end of the word). These nitrites are also quite toxic in their own right, and can kill fish just as fast as can ammonia. Fortunately, more bacteria, commonly referred to as Nitrobacter, can "eat" nitrites and convert them to a much less toxic form called nitrates (notice the "ates" on the end of the word). These nitrates can be unhealthy if allowed to build and build, but fortunately they are very easy to remove. We'll discuss how in a few minutes.

While the tank is developing a healthy colony of bacteria, waste products can build up. Ammonia can be very troublesome for new tanks. It is almost always responsible for the "white, cloudy water" syndrome experienced by so many newcomers. The white cloud consists of microscopic particles so small that they can easily slip through the little holes in the filter material. In other words, attempts to filter out the white stuff won't be successful.

Where do these beneficial bacteria come from, and how do you get them to grow - and quickly - in your new tank? Well, the bacteria you need are found throughout nature. Probably the best place to get a "starter colony" of beneficial bacteria is from an old, established tank. The bacteria you want to grow are found throughout an established aquarium. They grow on the glass walls of the tank, on the gravel, the rocks, the ornaments, and on the walls inside the filter. If you have a friend who has a healthy established aquarium, you might be able to talk him out of a cup of his old, dirty gravel, or an old slime-coated rock or ornament. Do NOT clean this gravel or ornament! That slime coating contains the bacteria you seek! If his gravel does not match your gravel, just put the slime-coated gravel in a cloth mesh bag and toss it into the corner of your aquarium. If his ornament or rocks don't match your décor, remember that they don't have to stay in there forever. Just position the rock or ornament in your new aquarium, and the beneficial bacteria will grow and begin to colonize your tank.

This process does not occur overnight. Before beneficial bacteria can grow in your tank, your gravel, rocks, filter, etc., must first develop a "slime coating" of their own. This takes about 30 days or so, and there isn't a lot you can do to hurry the process. Patience is required here.

There are, however, a few things you need to know about growing these bacteria in your tank. First, be aware that beneficial bacteria will not grow in very acid water. If the pH of your water is around 5.5 or below, your bacteria will not grow. They prefer a more neutral pH, somewhere between 6.0 and 8.2, with a neutral pH 7.0 probably being best. Another factor is temperature. Beneficial bacteria grow faster in warmer water. They will grow extremely slowly, or not at all, at temperatures below 74 degrees Fahrenheit. If your water is cooler than this, you will want to raise your temperature. Fish are usually happier at warmer temperatures anyway, so go ahead and turn up that heater so the water is around 80 - 82 degrees Fahrenheit. Finally, be aware that beneficial bacteria are "aerobic" bacteria. That means that they prefer oxygen-rich environments in which to grow. Knowing this, you can help the beneficial bacteria grow by adding an airstone or bubbling ornament to the tank.

Several manufacturers make "bacteria in a bottle" products. Much misinformation and misunderstanding exists about these products, and some people on either end of the argument become quite vitriolic when voicing their opinions. "Bacteria in a bottle works great, and speeds up the cycle to just a few days." Wrong. "Bacteria in a bottle is snake oil, and doesn't work." Wrong. "No evidence exists that these products are useful." Wrong again. "Bacteria in a bottle are a waste of money." Sorry, but still wrong.

Bacteria in a bottle products such as [brand names omitted- sorry], and a host of others do usually contain the bacteria we want in our tank. Trouble is, you can't just dump them in the tank and expect to have an instant useful colony of bacteria. Instead, think of these products as "bacterial seeds." That is, they do provide the bacteria we want, but your tank can't sustain them until it develops the slime coating we mentioned. Since bacteria can't survive in the water column, but must attach themselves to smooth, slimy surfaces, the bacteria we add from a bottle will live in the water for a few days. Ammonia and nitrite measurements will show an overnight reduction in ammonia and nitrites, proving that the bacteria are indeed working and removing ammonia and nitrites as they should. Unfortunately, a few days later the ammonia and nitrite readings will rise once again. What happened? Well, the bacteria could not find a "footing" on which to grow (no slime coat has yet developed in the tank), and so they died off after a few days. More bacteria in a bottle can be added, but this will have to be repeated several times per week until the slime coating becomes established. At this point, the bacteria can then grow in the tank, and no further additions of bacteria will be required because the bacteria can reproduce and replace themselves on a daily basis. All this will take around 30 days or so. Thus, no bottled bacteria products can "speed up the cycle." They just sort of help point it in the right direction, but it's still going to take around 30 days, whether you use gravel from an established tank or bottled bacteria products. There are no shortcuts.

Well, maybe there are some shortcuts. Remember the suggestion to get a cup of gravel from an established aquarium, or perhaps a rock or two? If these rocks came from a large tank with many fish, there is the possibility that the rocks do have enough bacteria on them to sustain a SMALL colony of fish in another tank, right from day one. Another trick is in maintaining a spare filter on a large tank with large, dirty fish. Do you have a 55 gallon tank of Goldfish sitting in the corner of your room? If so, you probably have a large, very authoritative filter on the tank, a large canister perhaps, or a big Hang-On-Back (HOB) filter. Have you considered adding a smaller filter, perhaps a smaller HOB filter or something similar? While it won't have a large effect on the overall filtration, this smaller filter will maintain a large colony of bacteria on its internal surfaces. If you then want to set up a smaller (10-20 gallon) tank some day, you can pull that smaller HOB filter off the larger tank, add it to the smaller tank, and the filter will be able to handle a significant fish load from day one. In fact, it may be capable of providing 100% of the bacteria needed for a modest fish load in a smaller tank, right off the bat.