I wanted to add some info to this process without taking away too much from the time spent into creating this thread. There have been numerous recent issues with the cycle stalling and seemingly taking longer than it really needs to. I have never used the steps mentioned below but have used a fishless cycle 3 times now and the result has always been fairly consistent. the only thing that hasn't been the same each time is how long it takes to complete....that will be different for every tank. Here is what I do once I have the ammonia and the tank has tested 0ppm ammonia:
1. Dose 1/2tsp, wait a minute or two and test. Keep doing this until 4ppm ammonia is attained. Remember this amount. DO NOT dose based on someone else's recommendation because not all ammonia bottle are the same and have varying concentrations of ammonia. It will take less to get to 4ppm with a higher concentration.
2. Stop testing for ammonia. It will drive you crazy if you don't. Just dose the ammonia daily and don't think about the ammonia level again. Dose about the same time every day.
3. On about the 5th day or so start daily testing for nitrites - can be done earlier if you desire.
4. Once any trace of nitrites show, cut daily dose amount in half and now dose ammonia every 4 days.
5. Keep doing that until nitrites test 0ppm.
6. Once nitrites are 0ppm, then
test ammonia again and make sure it has zeroed also.
7. You can test the system if you choose. Dose some ammonia and test for ammonia the next day, along with nitrites, etc....until it all disappears again.
I just did a fishless cycle on a 20L to verify this method as it worked for me twice before and just wanted another test to be sure before I posted here. My tank completed the cycle in 12days. On the 13th day everything tested 0ppm except nitrates. Every tank will be different and smaller tanks do not mean it will occur faster. My other 20g took a little longer but not much.
The Fishless Cycle
This article is intended for those of you who would like to establish a safe environment for your freshwater
fish before introducing any fish into your aquarium. As opposed to the method of cycling using a “hardy species” of fish, this method, when done correctly will not cause any harm to any of our aquatic friends.
Fishless cycling is considered by me and many others to be the most humane way of establishing the nitrogen cycle that is currently available to the aquarium hobbyist.
Rather than go into the different methods of introducing ammonia into the setup aquarium I’m going to focus entirely on using pure ammonia as the source. There are other ways such as allowing shrimp to rot or using fish food. The method of monitoring the progress of the cycle would be the same no matter what the source of ammonia. Also with the pure ammonia method there is no chance of introducing saprolegnia (mold) into your tank.
This article also will not cover the setting up of the tank and its hardware (that’s not what it is about). Also the method I will lay out here is for aquariums with out any live plants. I’m not saying it won’t work with live plants, just that since I have never had any, I claim no knowledge of cycling an aquarium where live plants are present.
What is needed?
In my opinion the most important tool needed for this process is something to monitor the progress of the cycle with a fair degree of accuracy. A good liquid test kit is imperative so you know just how much ammonia to add to reach the desired level and to maintain this level through out the majority of the cycle. Also with out a test kit it is impossible to know when the cycle has completed and it is safe to add fish.
There are many liquid test kits out there and they vary in price from around twenty dollars up to five times that amount and more. Fortunately the least expensive of these liquid kits is sufficient for the task at hand. I recommend the API freshwater
Master Test Kit. This kit has every test we will need to keep the ammonia levels where they need to be. Also included are tests to monitor nitrites, nitrates, and dare I mention PH. Put the PH test kit away and forget about it for now. You can use it once the cycle has completed. The PH should not be adjusted during cycling. This will just mess the whole process up.
Next thing needed is ammonia. No problem, right? Guess again. Not just any ammonia will work. Ammonia that is scented or has added detergents should never be used.
You will need to read the ingredients on the bottle of ammonia. If it lists anything other than ammonia it is the wrong kind. You should be able to shake the bottle with out the contents foaming at the surface is another way to test. Ammonia containing surfactants only may not foam up when shaken. There is a small consensus out there who believe ammonia with surfactants is safe to use for cycling. I do not subscribe to this theory. I recommend using only pure surfactant free ammonia. Pure ammonia also comes in different concentrations which make it hard to establish dosing parameters, i.e.: add one teaspoon per gallon to achieve a certain level. Don’t worry about the strength of the ammonia. There is away around this that will be explained later on.
You should also have a heater in your tank and a thermometer as proper temperature during the cycle is important. These items will also be needed after the cycle has completed if you plan on keeping tropical fish.
Get a note book. You will need to write things down. Many people (me included) keep a running log to keep track of water parameters, tank and filter maintenance and anything else you want to remember.
I think that covers the materials needed for fishless cycling. One place I know of to get the right kind of ammonia is Ace Hardware. I have also heard that Dollar Tree stores carry pure ammonia.
Okay here we go, the tank is set up. I recommend letting it run for 24 hours to allow all the “dust” to settle before starting. During this waiting period adjust your heater to bring your tank water temperature to 83-85 degrees Fahrenheit. The warmer temp will help speed things up just a bit. This is also a great time to test your tap water for ammonia, nitrites and nitrates. Let your cold water tap run wide open for 2-3 minutes to flush the line. Fill a clean well rinsed container of at least a liter in volume half way. Add the recommended amount of dechloranator (you do have some, right?) to the container. Let it sit 24 hours for the C02 to gas out and the water to stabilize. Run the full gauntlet of tests included with your test kit (yes you can even test the PH). Make sure you write all the results down. This has now given us a baseline on your tap water.
Tap water parameters will change through out the year. Water treatment plants change the amount of chemicals used from Summer to Winter. Also heavy rain or drought conditions can affect your water quality. It is a good idea to test your tap water several times a year.
Make sure you read and understand the directions included with your test kit. Follow these instructions to the letter. Not doing so will result in inaccurate, useless results.
Before adding any ammonia lets also get a baseline reading of the level in your tank. This time leave the PH test out. I’m going to say that ammonia, nitrite and nitrate all read zero in your tank water because everybody’s is going to be different. Just know that if your tank water shows any level of these three things they will affect your test results later on.
Dose the ammonia at one teaspoon per 10 gallons. Let the water circulate for two hours and test for ammonia. The goal here is to get the level up to 3-5ppm. If after testing your levels fall in this range that is great. If it is less than 3ppm add another teaspoon per 10 gallons and retest. Repeat the ammonia dosing until 3-5ppm is achieved. Write down the dosage you used to obtain this level. This is why the concentration of the ammonia is not important as mentioned earlier. If you should happen to over dose don’t panic. Replace some of the water in the tank with some of your tap water and retest. Eventually you will get it right.
Now just sit back and do nothing for 72 hours. Tell your wife/husband I said it was okay. (let me know if this works). No need to test during this time. The time has passed and it is time to start monitoring the progress of the cycle. Test your ammonia levels at least once every 24 hours. Once they begin to drop add the appropriate amount of ammonia to bring the levels back up to 3-5ppm.
Now that the ammonia levels have begun to drop it is time to pull out your nitrite test kit and begin monitoring both the ammonia and nitrite levels. Again testing should be done at least once every 24 hours. Keep dosing ammonia to maintain adequate levels (3-5ppm).
At some point your nitrites will peak at around 5ppm. At this time I recommend cutting your ammonia dosage by 50% and reduce the frequency of dosing to every other day. Monitor the ammonia levels closely! To high of a level may stall the cycle and prevent the colonization of bacteria. When nitrites begin to decline begin testing for nitrates. When nitrates begin to register you are getting close to completion. Continue to dose ammonia at the reduced level and monitor closely.
*(More dosing info at the end of article)
Your cycle has completed when you can dose the ammonia up to 4ppm and after 24 hours when you test the results are zero ammonia, zero nitrites and X ppm nitrates.
Do a water change to bring the nitrate level down to less than 20ppm. Do not do any filter maintenance or gravel vacuuming at this time !
Don’t forget to adjust the temp of the tank water to the appropriate range for the fish you plan on keeping.
The tank is prepared for fish now. A great benefit of this cycling process is that your aquarium has a large bacteria population and can support a greater initial bio load (number of fish). Do not wait to stock your tank after cycle completion as the bacteria will die off if an ammonia source is not present.
You should continue to monitor your ammonia and nitrite after introducing your fish into your aquarium. Better safe than sorry. After about a week of continued readings of zero for ammonia and nitrite you can quit testing for them.
Monitor nitrate levels and base the percentage of water changed out on the results of this test. Let’s say after a week of zero ammonia and nitrite you test the nitrate and the results are 40ppm. A 50% water change using replacement water with zero nitrate will result in a 50% reduction in the nitrate level. Your new nitrate level will be 20ppm. I would not recommend any filter maintenance at this time and light gravel vacuuming to avoid triggering a mini cycle.
The following week keep some of your tank water you drain in a bucket and clean your filter media in this water. Do not clean the bio media unless it begins to impede the flow of the filter. I recommend alternating deep vacuuming of the substrate and the cleaning of the filter. You should never deep vacuum and clean all of the filter media at the same time.
I have at least two filters on all my tanks. Besides improving water quality and circulation this allows me to alternate filter maintenance. Also in the event of a filter failure an established backup is in place and running. If you can do the same.
How long does this take?
Well let’s see. When the Earth was first formed it took around two billion years before the first bacteria showed up. If you have read the Bible God did it all in seven days (he must have had a real good bacteria in a bottle product!). So I would say some where between 7 days and 2 billion years. No, really it will take as long as it takes. Patience is the key here.
My best guess is somewhere from 21-28 days.
Use the time to research the fish you want to keep. Read all you can about the hobby. Participate in this forum. Post pictures of your tank, ask questions, help others along. The time will go by fast and the results are well worth the time invested.
If you have managed to read through all of this and have learned a thing or two, than I have accomplished one of my goals for writing this. My other goal was to completely waste your time.
Type at ya later,
Additional dosing instructions added 06/09/11 (Thank you Holly!)
The plan here is to maintain the ammonia levels at the level needed to feed the colonizing bacteria with out rasing levels to high. In a freshly set up system (no bio help what so ever) it is pretty much useless to test the ammonia for around 72 hours after the baseline has been accurately recorded. It will take this long for the bacteria to start forming.
You should have at this time a baseline reading for your tap water and a baseline reading for the tank water. You should also have recorded the initial dose of ammonia required to achieve the desired range (3-5ppm) Using this info you should be able to calculate the amount of ammonia needed to maintain this level.
Example: Baseline ammonia level of tank water was zero. After dosing one tsp for every 10 gallons your new levels were 2 ppm. Not quite there. You add another tsp per gallon and retest. Levels are now 4ppm. Perfect. It took two tsp to achieve the desired level. Initial reading was zero end reading was 4 and dosage was 2 tsp. Divide dosage (2) by change in ammonia level (4)=0.5 tsp. This gives us the dosage required to change the ammonia level by 1ppm, 1/2 a teaspoon.
In a case where the intial dose of 1 teaspoon per 10 gallons was enough to reach the desired level you divide 1 by 4 = 0.25 or 1/4 tsp per gallon would adjust the level by 1ppm.
Maintain the ammonia level dosing your calculated amount of ammonia as needed. As the concentration of ammonia varies by product the initial tank dosage is the best way I know of to account for this.
I couldn't just say dose "X" amount because with some products this would be way to much and with others not enough.
Hope this clears things up a bit.