Cycling Your New Tank
This article will explain how to cycle your tank, what cycling your tanks means, and some tips on getting it done properly.
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What is cycling?
Cycling is the process of establishing colonies of beneficial bacteria in your filter. Fish waste is basically ammonia and is toxic to your fish. Ammonia is kept from killing our fish by developing colonies of these bacteria that convert ammonia to nitrite. Nitrite affects the blood's ability to carry oxygen; so, it can also be toxic. Luckily, a second set of bacteria will colonize and convert nitrite to nitrate. Nitrates aren't generally considered toxic until they reach higher levels. Doing regular, partial water changes, using plants, or both removes nitrates. It usually takes 4-6 weeks to get large enough bacteria colonies to keep up with the ammonia and then nitrite levels. This is why it's always recommended that you start with just a few hardy fish. Feed them small amounts (what they eat in 30 seconds) once a day or even once every other day until your ammonia and nitrite levels have risen, and returned to 0. Then you can slowly start adding fish every few weeks until you get to the expected bio-load for the tank. The term bio-load refers to the maximum amount of ammonia your bacterial colonies will need to process when your tank is fully stocked. In other words, the maximum amount of fish, food, and waste your tank can handle.
What happens during a cycle? (why is my tank cloudy?)
It's normal for your tank to initially become cloudy. The beneficial bacteria that digest the fish waste colonize only on the surface areas in your tank. They form in a layer, one deep, on any surface that has oxygenated water passing over it. The cloudiness in the water is an initial bacteria bloom that you'll see as the colonies start to establish. Don't panic and try to get rid of it with chemicals or a UV sterilizer, you'll just slow the process down.
What is Fish-less cycling?
If you don't want to use fish to cycle the aquarium, you can do a fish-less cycle. By adding pure ammonia immediately to the level of a full bio-load, you can drastically jump start a process that would normally take the fish weeks to create. Because you add an amount comparable to a full fish load, you can fill the tank immediately with all of the fish you want to keep, as soon as the cycle is finished.
How do I do Fish-less Cycling?
Fish-less cycling sounds very involved and scientific but it's really not too difficult. One of the biggest challenges can be obtaining pure ammonia. You want to make sure you get a type without foaming agents, colors, or scents. That will usually be the cheapest brand available. Add ammonia to the aquarium to reach a level of 5ppm, and keep track of how much ammonia that takes. Add that same amount daily until you start to see nitrites, then reduce the level to the amount you had been adding. Once both ammonia and nitrite read 0, you can do a large volume water change to reduce nitrates to a manageable level and add your new fish!
Cycling a tank with fish in it.
If you are cycling your aquarium with fish, adding Amquel can detoxify the ammonia for your fish, if it reaches levels that would stress your fish. Be sure you don't overfeed during this time. Uneaten food can create an ammonia "spike", which can permanently damage their gills, if your fish manage to survive it. Ammonia will make fish itch, gasp at the top of the water, show inflamed, red gill tissue, and can cause septicemia (red streaks in their fins) along with numerous other systemic problems. Be sure to keep track of your levels! Water changes of 30% will help keep your fish from being as damaged by the levels of ammonia and nitrite, or help you get levels under control if you've discovered you added too much ammonia by accident with the fishless method. If you are doing a fish-less cycle, I definitely have to recommend not using Amquel, Amrid, or any other additive that is going to interrupt the ammonia availability. You'll risk slowing down the process.
How about bacteria in a bottle?
There are many available products that claim to contain cultures of the bacteria needed for an established aquarium. In my experience, most of these products do nothing more than shorten the process by a few days, if even that. Bio-Spira, by Marineland, is the only "bacteria in a bottle" that I had really noticeable results using. I definitely recommend it for speeding up the process if it's available near you. Filter media from an established tank, gravel from a tank with an under gravel filter, or even the brown nastiness from a filter cartridge or sponge rinsed in aquarium water will all aid in jump starting those bacteria colonies. "Borrowed" media can be placed in a filter mesh bag (no nylons, they can have bacterial agents in them), then added to your new aquarium. Doing this can shorten your waiting period to a matter of days, rather than weeks for the cycling process to complete. (Yes, I know the idea of messing up your beautiful new aquarium is hard to take, but it DOES do wonders!) I personally tend to be into instant gratification so this part of the process is very important!
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