Vote for TFF UK


Recent Topics


Black Angel - Pic 1

Posted by GazNicki

Ammonia Calculator

Articles on TFF UK

Donate to TFF!

If we have been of help please consider making a Donation to TFF UK

Or sign up to a quarterly subscription at £10 every 3 months

Every Little Helps


  • Total Posts: 845215
  • Total Topics: 66782
  • Online Today: 48
  • Online Ever: 340
  • (November 03, 2012, 08:29:45 PM)
Users Online

RSS Feeds

Setting up your new aquarium

Setting up your new aquarium

New Tank Syndrome is the number 1 cause of fish death. If you take the time to read this and follow the steps, you will not have to deal with new tank syndrome, and you will create a healthy environment for your fish.

This article won’t deal with tank specifics- which tank to buy and what equipment to get etc. This will be covered elsewhere. These steps are for once you have everything you need- a tank, stand, filter, lights and heater (although the procedure is the same for coldwater tanks as well). Got all that? Fantastic!

When we set up a freshwater aquarium, our goal is to recreate as best we can the environment which fish live in out in the wild. It’s important to remember- most of the bodies of water that wild fish live in (lakes, rivers, ponds etc), have been around for hundreds, if not thousands or even millions of years. They are mature and stable environments, which in themselves are their own self- sufficient eco- systems. Your new tank is not- it is a sterile and man- made construction.

When you start reading up about water chemistry and all the different parameters and variables, it can seem so daunting that it’s easy to get overwhelmed, and very easy to just give up before you’ve even started. Don’t. There is one basic and fundamental process to understand, which, once you get your head around it, is at the core of maintaining a healthy environment for your fish. This process is the Nitrogen Cycle. Don’t worry- it’s really not that complex.

The Nitrogen Cycle

As we know, a brand new tank has nothing inside it. What keeps a tank healthy and safe is GOOD BACTERIA. This is the one most important aspect of your tank’s filtration- the good bacteria colonies. Our aim is to cultivate colonies of good bacteria within the filter of the tank, which will convert deadly toxins into something harmless.

There are three stages in the nitrogen cycle.

Note: Nitrite and Nitrate are two very different things.

1)      Ammonia stage. Fish produce waste, which is a source of ammonia. Ammonia is very toxic to fish, and can kill them very quickly. Ammonia is also produced from the decay of plant matter, and from uneaten food in the tank.


2)      Nitrite stage. Good bacteria number 1 (Nitrosomonas) converts ammonia into nitrite. Nitrite is also toxic to fish, and kills them.


3)      Nitrate stage. Good bacteria number 2 (Nitrobacter) converts nitrite into nitrate. Nitrate is much less toxic to fish, and is removed with each weekly water change.

Basically, fish produce ammonia in their waste. This ammonia would kill them, if it weren’t removed by our good bacteria number 1. Our good bacteria convert the ammonia into nitrite. The nitrite would also kill the fish, if it weren’t for our other friend, good bacteria number 2. He converts the nitrite into nitrate, which is only toxic to fish in very large quantities. Weekly water changes keep the nitrate level to a minimum, so it doesn’t become harmful.

So, as you can see- we need lots of good bacteria number 1 and number 2. As much as possible. Once we have loads of good bacteria 1 and 2 living in our tank, we will be ready for fish. So how do you create colonies of good bacteria in your tank? Through a method known as The Fishless Cycle.


The Fishless Cycle

These are the steps you need to follow to make your tank safe for fish. The purpose of the fishless cycle is to cultivate enough good bacteria, so that your tank can go through the nitrogen cycle. This will make it its own eco- system.

 Remember our friend good bacteria number 1? Remember what he eats? Ammonia. He needs ammonia in order to survive. So, the fishless cycle involves adding ammonia to your new tank, in order to feed the good bacteria, so it can multiply, until there are enough good bacteria to keep our fish healthy.

You will need:

  • Dechlorinator. This makes tap water safe for fish.


  • A test kit, to test for ammonia, nitrite and nitrate. The best beginner’s test kit is the API master test kit.


  • Pure ammonia. It is extremely important that the ammonia you add to your tank is just ammonia and nothing else. “Jeyes Kleen- Off ammonia” is the most readily available online.


  • A Dosing Syringe or similar to measure out small quantities of liquid.


  • It will help if you can find some mature filter media from an established tank, as good bacteria will already be living inside this.


  • Patience.


Just google the names of the products- you’ll find them straight away. I’m not posting links as shopping websites are constantly changing. If you want mature filter media, you can make a thread on TFF and see if someone local to you has any spare. 

Got all those things? Read on.

Before you get anything wet, choose your substrate and ornaments etc. NOTE: Once you have laid your substrate down, you are stuck with it!! Think carefully and be patient. Make sure you clean your substrate thoroughly with water until the water runs clear, before you add it to your tank. Add the ornaments too, before you fill the tank with water.

Fill up your tank with water. Dechlorinate the water. Follow the dosing instructions on the bottle. Wait for the water to settle. Check your tank over for leaks. Once you’re satisfied it’s in a good condition, turn on the filter, and test the lights…

*Note: Adding aqueous ammonia can raise your pH. You should test your pH as well as everything else, just make sure it doesn’t go above 8.6- your cycle may stall if it does. Also, if you cannot find aqueous ammonia, you can also use Ammonium Sulphate or Ammonium Chloride. However dosing will be a bit of guesswork, and I recommend you use liquid ammonia if you can find it.

Now the fishless cycle begins.

1)      Turn your heater up to around 80 Fahrenheit/ 27 Celsius. This will help the cycle along. Make sure your filter provides good flow around the tank.  Work out how your filter works, how many sponges there are etc. If there is a carbon sponge in the filter, remove it. It will only slow you down.


2)      Test your tap water so you know what you’re dealing with. It won’t have ammonia or nitrites, but test it for nitrates, pH, and KH and GH if you can. If your tap has a very low pH, say lower than 6.6, you should read the note at the end of this article before you go on to step 3.


3)      You want to bring your tank ammonia level up to 4 PPM. You work out how much to add by using this calculator. http://www.tropicalfishforums.co.uk/index.php?page=ammonia_calculator

Jeyes Kleen Off ammonia is 9.5% so change that value on the ammonia calculator. Then adjust your required and existing PPM (existing PPM will be zero), to find how much ammonia to add.

Just remember to account for displacement. For example, if your tank is 125 litres, but you have ornaments in there, you probably only have around 100 litres of water in there.


4)      You should be testing your ammonia daily to ensure you’re adding the right amount. Once you’ve got it at 4 PPM, leave it there. Test it daily until you see it start to fall. As soon as it falls to 3 PPM, start adding more ammonia to keep the level at 4 PPM. Keep doing this, and start testing for nitrites.


5)      Keep testing ammonia and nitrites daily. As soon as the nitrites read above 0.25, reduce the amount of ammonia you are adding, so that you maintain the ammonia level at 2 PPM, instead of 4.


6)      Maintain the ammonia level at 2 PPM for about a week, while testing for nitrates. Your nitrates should start to rise.


7)      After about a week, do this: add enough ammonia to bring the tank ammonia level up to 2 PPM. Test both ammonia and nitrite. Make a note of the time. Test again 24 hours later. If both the ammonia and nitrite have fallen to zero within 24 hours, then bring the ammonia back up to 2 PPM and repeat the test the following day. Then finally, repeat the test for a third time, to ensure that the ammonia is really falling to zero within 24 hours.


8)      The day before you add any fish, do a very large (80%) water change (using dechlorinator of course). This is to remove the high nitrates. Then adjust your heater back down to an acceptable temperature (25). Add ammonia to bring the level back up to 1 PPM, so your bacteria don’t starve.


9)      The next day, test for ammonia, nitrite and nitrate. Ammonia and nitrite should be zero. Nitrate should be very low. If your readings are ok, you can now fully stock your tank.


10)   You’re finished! Well done for completing the fishless cycle. It’s still important to test daily for the first week after adding fish- especially for ammonia and nitrite. If for some reason you get a spike in either, do a 50% water change and keep doing this to keep the levels below 0.25.



*Note for low pH tanks- the cycle will stall if the pH drops too low. Just add a small amount of bicarbonate of soda to the tank (one teaspoon for every 50 litres of water), and this will bring your pH back up to an acceptable level.

Share on Twitter! Digg this story! Del.icio.us Share on Facebook! Technorati Reddit StumbleUpon

Articles in « The Aquarium »

Comments *

1) Re: Setting up your new Aquarium
Written by hayleyj101 on January 01, 2013, 08:02:07 PM
Thank you so much for writing this post - I am going to follow it very carefully.  I am determined to make this hobby work and havea  successful tank.

I will probably have a few questions if you don't mind!  Here's my first three!

1)  Amazon have no stock of the Jayes Ammonia - is this the same thing:  http://www.amazon.co.uk/Klenoff-Household-Ammonia-500ml/dp/B000TAWBLC/ref=sr_1_fkmr1_1?ie=UTF8&qid=1357070129&sr=8-1-fkmr1

2)  What is mature filter media

3)  When I do a water change - do I just add cold tap water to the tank and add the water treatment at the same time?  What if there are fish in there during my water change - what temp does the water have to be when I add it to the tank?

Sorry for the silly questions, I am very new to this!

Thank you! x
2) Re: Setting up your new Aquarium
Written by Sacha on January 01, 2013, 11:03:02 PM
Hi Hayley,

1) Yes, that's exactly what you need.

2) Mature filter media is anything that comes from an already established filter. So if someone has had a tank set up for a year, and they give you a sponge from their filter, then you put that sponge into your own tank, you are adding good bacteria from your friends tank, into your own tank. This speeds up a cycle.

3) It's very important not to shock your fish through temperature shock. You should match the temperature of the new water to the temperature of the tank. Your fresh water will probably be too cold, so maybe add some boiled water from the kettle, to bring the temperature up to the same temperature of the tank. Just fill a bucket of tap water and a bit of boiled water, to bring the temperature up a bit, then add the dechlorinator to that bucket. You should have some way of measuring how much water you're adding to the bucket. I have a big tub, and on it, I have labelled with a permanent pen "10 litres", "20 litres" and "40 litres", so I can see how much water I am adding to the tank.

Also, your fish should always be in the tank during a water change. You shouldn't take them out of the tank. You should also never do a full water change. 50% should be the maximum amount of water you change at once.

I hope this helps a bit but let me know if it isn't clear. Maybe better to just make a thread in the forums, instead of here.
3) Re: Setting up your new Aquarium
Written by hayleyj101 on January 02, 2013, 12:52:11 PM
Thankyou so so much for all your help and advice x
4) Re: Setting up your new Aquarium
Written by andrew197 on January 03, 2013, 04:03:38 PM

What a fanstastic article. I have read it a few times and just enjoyed the read! Thank you.

I have a couple of questions as a newbie to keeping fish and I have a tank to collect in the next couple of days and want to get things completely right before adding fish (obviously).

My queries are different as the tank I am getting has been used (up to literally today/tomorrow until the move their fish to their new tank). It comes with its own internal filter and an additional external filter. What, specifically, do I need to do with this in terms of the cycle?

I have just systematically gone done the list you provided and bought the items - great fun!

Thanks very much

5) Re: Setting up your new Aquarium
Written by Sacha on January 03, 2013, 04:17:11 PM
Hi Andrew,

Thanks for the comments- glad you enjoyed the article.

The person you are getting the tank from- can you ask them how long the tank has been running with fish? If it is a long time, longer than say a couple of months, in theory you shouldn't have to cycle it at all. The filter should already be cycled. Just make sure that the filter stays wet, otherwise the bacteria might die.

I'm sorry you bought the items- you probably wont be needing the ammonia. Maybe cancel the order?

If you could find out exactly how long the filters have been running for and let me know, that would be great. It's probably better to send me a private message though instead of clogging up this space.


6) Re: Setting up your new Aquarium
Written by andrew197 on January 05, 2013, 08:08:52 PM
Just a quickie - can a tap, safe type product such as Biotopol - Makes water safe be used instead of a bog-standard dechlorinator. I have the former and I ready to go if yes. If not, then I am waiting on a delivery around Wednesday for dechlorinator. I would like to get started on my cycle asap.

7) Great Article!
Written by SeanFace101 on March 12, 2014, 12:33:29 AM
This is a really good informative article. I didn't have a clue about the different bacteria, not even about any fishless cycle either. Since reading this I now have my water testing kit order and will start things when I have tested the water. Thanks.
8) Re: Setting up your new Aquarium
Written by StueyMac40 on June 28, 2014, 09:29:53 AM
This info is blimmin brilliant - thank you so much!
9) Re: Setting up your new Aquarium
Written by Jimmer Gray on October 17, 2014, 02:28:01 PM
Hi, this is exactly the info am looking for great article. But I have one question on this.
If I can't get mature filter media what steps will I have to take to make a good health fishless cycle.

10) Re: Setting up your new Aquarium
Written by plankton on November 25, 2014, 11:50:46 AM
Please note that we have discovered that the cycle is more efficient if, in instruction 4, you only top up to 2ppm once the concentration falls, so it sort of combines with instruction 5. :)
If you do use mature media, then only start at 2ppm, not 4ppm.
11) Re: Setting up your new Aquarium
Written by strider60l on July 10, 2016, 05:43:12 PM
Thank you for this post sacha its really good :D

I only have one question, in regards to the fishless cycle you say to take a carbon filter out, i have a new filter sponge i bought on the cheap from a discount crate haha would i be better to replace the carbon with the sponge instead of just leaving a section of my filter spare ??

Thank you
12) Re: Setting up your new Aquarium
Written by Ammie1 on February 06, 2017, 08:55:05 PM
Hi Sorry to jump on this post but im looking for some advise please. We set up at 60litre tank for our daughter 3 weeks ago as per aquatic shops advise, all water was fine. We toom a sample down on saturday and got the ok to get fish. We got 6 guppies and 2 clown pleco, all were fine then last night and today 1 of the flame guppies were staying an inch off the bottom, he was swimming very fast but not actually going anywhere. I phoned the aquatics shop to get some advise (we already did a white spot treatment on them the day we got them, 2nd dose is wednesday) she told me to bring him in amd they will quarantine him and to get another fish, we did that although sad to leave Jasper behind, she also advised me to get some aquatic salt and said 1 teaspoon per 5 litres to me. So i got home reintroduced the new fish and put 10 teaspooms of auatic salt in, all fish seem fine and are swimming happily. I did some reserch about adding salt later on and i have read its 1 teaspoon per 5 gallons!!! I have done a 6% water change as my partner said it will stress them out if i do anymore. Will my fish be ok, i have been so carefull and im now scared that i may have harmed them. Any advise will be great please.
Commenting option has been turned off for this article.