The tank is set up and looking great or empty. Maybe you are doing a fishless cycle and adding ammonia or maybe you have added a few fish and now you are waiting for the tank to finish cycling. It feels like it takes forever. How long has the tank been set up? Can't only be a week can it? Well, it is important that you don't add fish before the nitrogen cycle has completed, but at the same time there are some things you can do to help the nitrogen cycle get done.

What is the nitrogen cycle?
An aquarium needs a bunch of good bacteria in order to be safe for fish. Fish food, plant matter (if you have live plants) algae, and fish wastes (yep, they make their own home fowl) all contribute to poison in the water. This is only acceptable because a tank that has been cycled contains bacteria that break the ammonia into nitrites and then it contains bacteria that break down the nitrites into nitrates. Nitrates aren't perfect, but it takes a lot more of them to kill your fish so regular water changes are enough to take care of this issue. You have to give your tank time to grow this bacteria either while there are a small number of fish in there (see Aquarium Set Up: The Nitrogen Cycle for more information) or while there aren't any fish in there while you are feeding the bacteria (see Aquarium Set Up: Cycling Your Tank Without Fish). You can't just run your tank and wait for it to happen and you can't just rush out and buy all the fish that you want.

Things You Can Do.
While you should always take the time to monitor your tank with a test kit and you should use it to let you know when the nitrogen cycle is over in your tank, there are things that you can do to get the process started and going strong.

  • Seed your tank. There are a couple of ways which you can seed your tank, however they all require that you have access to an established tank. If you have another tank you can use that one provided your water quality is good and your nitrogen cycle is over there. You can borrow from a friend if you feel confident that their tanks are well taken care of. Some local fish stores will also provide you with seed material if you ask. Just make sure it is a store you can trust. Seed materials include filter material (sponges, floss, or fiver materials are all great places for bacteria to grow). Take all of it or part of it and place it in the new filter. You can also take gravel and place it in a washed (without soap) nylon. Put this in the filter or in the corner of the tank after you have tied it off. Live plants can also help because they are usually covered in bacteria as well and decorations, drift wood, or rocks that have been in a tank can all help.
  • Keep it warm. Bacteria likes the warmth and it will help them grow more if you keep it at about 80 to 82 degrees in there. You will need to make sure that any fish that you have added can handle it that warm for an extended period of time.
  • Aerate. Oxygen is another helpful part of the process. It is a good idea if you make sure that you are adding as much air as possible. Leave the water levels down just a bit from the filter so that more air gets in and get the biggest air option available to you for more air. This is very helpful, but you need to make sure that you aren't adding too much motion for fish that don't like the water flow. Be careful with this as well as the temperature and tailor it to the fish that you have put in there (if you have fish in there).

Considering a Product.
There are a huge number of products out there and mixed reviews and ideas about whether or not you should use them. If you really need a faster cycle you may want to consider them. First see what is available in your area and then do some research to make sure that it will work and that it will help. Many of these products don't really help the nitrogen cycle and can even cause it to take longer because they don't provide the time for all necessary bacteria to grow. Do your research to make sure that you aren't wasting money on a product that doesn't really work.

There are a few things that you should avoid doing if possible because they can cause a great deal of damage to your tank and will make it harder for the nitrogen cycle to complete.

  • ...changing your filter media. Depending on what type of filter you have they may suggest that you change it out part way through, especially if you have a messy substrate. However, this media is where your bacteria has started to grow and it is important that you don't change it out until you have a well established colony.
  • the walls of the tank. A few weeks can be the start of some interesting, but not always appealing looks going on. You may see a film of slime appear on your decorations or your wall. You may see algae begin to grow depending on what foods you are feeding and what light resources they have. However, no matter what you see growing on your filter you should avoid cleaning it! Your tank walls and decorations are becoming homes for your helpful bacteria and you want to make sure that you aren't cleaning it off!
  • ...water changes, whenever possible. If you have fish in there then you may need to do a partial water change part way through. In fact, it is recommended that you do a 10% water change ever other day or every three days. However, it is best to leave it alone if possible. You need to make sure that your ammonia or nitrite levels aren't so high that your fish are dying left and right, but if you can get away with it you want to make sure that you are letting the bacteria grow.
  • ...avoid most chemicals. You need to add a dechlorinator if you are adding tap water, however you don't want to try and adjust the pH at this time, you don't want to buffer your ammonia (that's what you are feeding your bacteria colony) and you don't want to get carried away adding all sorts of chemicals. Keep it simple and try to avoid adding chemicals to your tank whenever possible.

You can speed up your nitrogen cycle, but it should be noted that it isn't going to go away and you shouldn't pile the fish in there because you want to. Instead do things to help it and keep an eye on your numbers. You can add new fish when your numbers look good!