Step One: Cycling
If you ask a pet store employee if you can have fish right away after setting up a tank, a good employee will tell you yes. A nice fish keeper will tell you that you need to cycle the tank, or you will be coming back to get more doomed fish soon.
The cycle is when an aquarium is readied to support life. A newly setup aquarium is incapable of supporting any kind of life, as it does not have the correct bacteria and such in place to convert waste into less harmful forms. This change is a constant cycle in an aquarium, but the first time is the important one.
In a cycled aquarium fish excrete ammonia, which is eaten by bacteria and converted to Nitrite. Other bacteria feed on the Nitrite and turn it into less toxic Nitrate. Nitrate is removed by plants and water changes. Plants prefer to remove ammonia however.
In an uncycled aquarium fish excrete ammonia and it stays as ammonia. It will burn the gills of any fish in the tank, and if it gets high enough kill them all.
There are two ways to cycle a tank. Most other ways are just variations on these two. The first is fish less cycling, and the second is cycling with fish.
Fish less Cycling
Materials:
- Clear Ammonia (should not foam, or have colors or dyes added)
- Ammonia, Nitrite and Nitrate Test kits
- Water De-chlorinator (or one that works with Chloramine, depending on your source water)
- Tank, fully setup, but with no animals in it.
- If you can decorations, gravel, or filter media from an already cycled tank
- If you are going to keep live plants, add them now. They will speed the cycle.
Time: From 9 days - 3 weeks
The first step is to add ammonia to the tank. Add enough that the test kit measures ~ 5 ppm. Remember how much you had to add to get that amount, as ammonia comes in very different concentrations. Add the same amount every day. After 3-4 days begin testing for Nitrite, but continue adding Ammonia.
When nitrite appears wait for it to spike, i.e. no Ammonia 24 hours after adding it, but tons of Nitrite. Cut the Ammonia dosage by half and begin testing for Nitrate. It takes longer for Nitrate to appear than Nitrite. When Nitrate appears Nitrite should disappear.
After you have Nitrate, test carefully to make sure all Ammonia you add gets converted, then do a massive water change with properly treated water. (Treated water is water with a de-chlorinator added so that you will not lose the effort you just made due to chlorine or chloramine in tap water. ) Now add fish. You can normally nearly fully stock the fish tank now that it is cycled, just stop adding ammonia when you add fish, and make sure there is no ammonia or nitrite present before you add them.
Cycling with Fish (Traditional Cycling)
Materials:
- Some fish you don't like (They're going to get their gills burned so won't live full life spans)
- Fully setup aquarium
- Water De-chlorinator (or one that works with Chloramine, depending on your source water)
- Ammonia, Nitrite and Nitrate Test kits
- Time
- Buckets for twice weekly water changes
Time: 4 - 6 weeks
Add several fish you do not care for, as they will often be very damaged by the cycling. Common choices are danios, or feeder goldfish.
Test the water, and when Ammonia begins to appear, start your water changes. You want to keep the ammonia as low as possible, because ammonia kills fish. The main reason this method takes so long is the water changes that continue to dilute the ammonia and keep the fish alive. The water will slowly go through the same cycle as in Fish less, but don't forget that Nitrite is also very poisonous to fish, and that level needs to be kept very low as well.
Once you get Nitrate, your cycle is done. Do a large water change to lower the Nitrate level. Now you can return the fish you used to cycle, and get only as many fish as you returned. Or you can add a few fish every few weeks because the bacteria only grew enough to process so much fish waste, so more than its expected amount would just start the cycle again.
Bacteria in a Bottle
For years there have been bottles of products saying they will solve your cycling problems. Ninety percent of them do absolutely nothing. They can't do anything because the bacteria you're trying to grow needs oxygen and most of these products are in sealed bottles. Recently a newer product was released that did at least speed up cycling. It was refrigerated, and supposedly did work. I slowed down my hobby about that time and never got to try it. It was also more expensive than all the useless products. I've lost my links to the product as it was a few years ago, and I can't at all remember it's name.
Setting up Another Tank
I haven't had to cycle a tank since my first two setups. if I'm setting up a new tank I take some gravel from an established tank, some filter media and some piece of decor, driftwood is ideal. All these things help to very quickly colonize a new tank with bacteria. As long as I stock lightly and feed sparingly for the first few weeks the fish are fine and the ammonia and nitrite are barely detectable.
Keeping the Tank Cycled
You wouldn't think this would be an issue, but I had tons of experience with it at the pet store. Customers would come in complaining of having cloudy water for months and it never got better. These same people often had algae blooms as well.
Under these conditions there were often two problems. One, they were following the manufacturers ideas on replacing filter cartridges. Filter manufacturers want you to replace the filters so they can get more money, not because it is in the best interests of the fish. If you change the filter when they want while cycling a tank you will keep loosing the majority of your bacteria and restarting over again. yes, nitrifying bacteria lives everywhere in the tank, but it especially like the filter because the water all moves through it and it stays oxygenated.
I use aquaclear hang on filters mostly. I have foam blocks in all of them. Occasionally I add ceramic filter pieces as well. I never take this foam out to throw it away. NEVER. When I do a water change if the water flow is significantly lowered in the filters I turn them off and squeeze the filters out in the change water. I then put them back in the filter. That is all I do. I never buy new foam unless I want to steal some of the existing foam to set up a new tank. I even retrofit other hang on filters to use foam. I don't chemically filter unless I need to remove a medication, and I haven't had to medicate in an established tank in years due to using ISO tanks.
Two, they were massively overfeeding. Most fish have stomachs about the size of their eyes. They do not need massive amounts of food unless they are fry or you are trying to breed them. Feed them only what thehy will completely consume in a few minutes.
Links
- http://www.aquahobby.com/articles/e_fishless.php Aquahobby article.
- http://www.csupomona.edu/~jskoga/Aquariums/Ammonia.html -- Updated article.