What is cycling a tank? Cycling a tank is building up a supply of beneficial bacteria in your filter. It is VITAL you have this bacteria in your tank to break down waste, without it, your fish WILL die. Water testing is necessary in this stage. Way too many people, even very experienced people do not know this concept. Properly learning it though, will almost guarantee your success. If anyone has ever told that in order to cycle a tank, all you need to do is let your filter run for a days, please forget that. That is false. It is important to know that nothing is really happening to the water in the tank; just your filter is getting colonized with bacteria that break down wastes such as ammonia and nitrite. In order to start your colony, you must supply some type of waste into your tank. All you need to do is supply ammonia and the bacteria will start to grow. Cycling a tank is tough for the beginner but you will get through it. Too many people don't even know about cycling so they attribute deaths to factors that aren't issues. Reading this article puts you at a HUGE advantage over the beginner who sets up their tanks and throws in fish. Below are the different methods which I will explain. Read the very bottom for tips to reduce time.
Fishless Cycling- What I highly recommend because you aren't risking the lives of anything while your bacteria colony grows. In this method, you add liquid ammonia found at a grocery store. Ammonia and nitrIte is toxic but it supplies the bacteria to grow. So remember this: Before you add fish into your tank, you must slowly build up the bacteria supply because it is the bacteria that breaks down the fish waste.The bacteria breaks down waste in this order. ammonia--> nitrIte--> nitrAte. Ammonia and nitrite are deadly while low nitrates is fine and unavoidable. The bacteria and your filter will make the established tank have 0 ammonia and 0 nitrates while you must do water changes to bring down nitrates, water changes will be talked about later.
1. Setup your tank with heater, filter, substrate, conditioned water ect.
2. Obtain liquid ammonia WITHOUT surfecents. When shaken, it should not bubble. I got some at price chopper, I'd recommend getting that so this guide will work exactly. It come in large bottle, maybe 2 L found in the cleaner section.
3. Now, you want to add ammonia until your tank has 5 ppm. Use your test kit. This will probably be around 3-5 mL per 5 gallons. Note a teaspoon is around 5 mL. This does not have to be exact but record how much ammonia it took to get to 5ppm ammonia. Now, put this amount in the tank once a day. At a week, start testing for nitrItes. Once you detect nitrItes, cut the dose in half. The cycle is done once the ammonia and nitrIte are at 0. This will probably in the 2-4 week range. Test high in nitrAtes is expected and normal. Stop the dosing.
4. Do a large water change, preferably 100% to remove all nitrates so you start fresh. Do not do water changes prior to this.
5. Your filter is now properly cycled. Adding in fish plus fish food will basically replace the liquid ammonia so the bacteria continue to sustain themselves and keep your water good. Using this method, you can add in all your stock at once which kind of rewards your patience but also benefits fish that are territorial.
*Note* you can use fish food/shrimp whatever instead of liquid ammonia, although it can get quite messy and isn't entirely recommended. Use the guide to get the same ppm, but you'd have to wait until it breaks down into ammonia so that's one of the downsides.
Cycling with Fish-This is the method commonly used years ago but I really don't recommend it. Doing this, you put fish in as soon as the filter is running and slowly add a few fish in every week or two until your stock is full. Doing this, you are pretty much exposing them to the high ammonia and nitrites, greatly increasing death rates. Exposing them to high ammonia can have long term affects as well so you really shouldn't do it. I know it's hard to opt for the fishless cycle because you will be weeks with an empty tank, but really doing that is a GREAT first step to success in the hobby. I would say that 80% of fish deaths do occur in the cycling stage.
1. Setup the tank with filter, heater, conditioned water ect..
2. Add in a few small hardy fish.
3. Now here is a balancing act. Of course, you must feed the fish but in order for them to survive, ammonia levels cannot be too high. Because the filter isn't developed with bacteria, ammonia will be through the roof. But you do need some ammonia to start the bacteria colony. Eventually after maybe a month, ammonia and nitrite will come down to 0. Note during this month, your fish are suffering.
4. Whenever I encounter someone who has fish in an uncycled tank, I always tell them to reduce feedings to once every other day, not get anymore fish, and do 50% water changes as often as possible. Trying to keep fish alive in an uncycled tank is pretty much survival mode. You must do all this work and hopefully the fish survive. Really, go with the fishless cycle and save yourself the worry and don't hurt the fish.
Like stated before, the entire point of the cycle is to develop a bacteria colony. Now there are some ways to introduce a colony in your tank which may drastically quicken the cycle. You can:
1. Introduce a filter pad or developed media from an established tank. If done right, the new tank may be insta cycled. Squeezing a used filter pad can help too. To test if the new tank is good, add in some food and see if any ammonia or nitrItes show up; if not, then you should be good.
2. Add some developed substrate. This works alright. Add in some gravel and hopefully the bacteria transfers over. Note: transferring water does nothing. Bacteria doesn't live in the column, only on things.
3. Some products work in boosting the cycle. I have a hit miss history with stability and no success with big al's or anyone else's "bacteria supplement." I have heard nothing good about Cycle either. Bio-spira or other 'live' supplements are likely to be the only ones that actually work but they are expensive to buy and ship, and can be rendered useless if unchilled at any point. If I were you, I'd first try to get an established filter pad and then try out stability. Either of these, you'd use the fishless cycle guide above but they should quicken all aspects.
Next will be fish descriptions.