How to Do a Fishless Cycle

Step-by-Step Guide

1. 1

   Step 1: Set up your tank

   The level you choose is personal preference.
   
   Using 2ppm is not usually problematic during a cycle and is probably more common.
   
   Some choose to use a slightly higher level so they can house more stock when complete, but high ammonia can cause a cycle to stall and play catch up sometimes, so keepers must be aware.
   
   Use pure ammonia (sometimes called "janitorial ammonia".
   
   Some household-cleaning ammonia has dangerous chemicals and scents added.
   
   It's become harder to find since 9/11 (bomb making) and at a push fish food can be used
   - a large handful in a stocking
   - but this is not as accurate to read/dose.
   
   There are a few calculators on the web (for example, on the Fish keeping website www.fishkeeping.co.uk or PFK) which require you to know the volume of your tank and the daily ppm of ammonia you have chosen in the tank
   - very helpful. ,, At this point the filter contains bacteria that break down ammonia into nitrite, so the cycle has commenced.
   
   Keeping a cycling diary is recommended so you can plot the changes/patterns emerging. , Keep testing for ammonia every 24 hours and now test for nitrite too. , Nitrite is often the most annoying reading as once it drops it will linger at low levels until sometimes just a few days before the end of the full cycle. ,, This will keep the bacteria from dying.
   
   Then, do a large water change (70-90%) to get your nitrate under 40ppm.
   
   Once the fish are added, continue to test the water for both ammonia and nitrite to ensure that no spikes occur.
   
   Be aware that tank pH can swing around quite a bit during these 4 weeks.
   
   Not unusual.
   
   Worth keeping an eye on it.
   
   If pH falls to 6 or below, this can cause a cycle to stall but there are easy ways to rectify this.
   
   A good fish-keeping forum will be able to advise in detail on a bespoke, tank by tank basis.
2. 2

   Step 2: but do not add any fish.

3. 3

   Step 3: Leave the tank running for 24 hours to ensure that the equipment is working as it should be and there are no leaks.

4. 4

   Step 4: Calculate the volume of ammonia required to raise the level in the tank to 2-4ppm.

5. 5

   Step 5: Add the required volume of ammonia to the tank.

6. 6

   Step 6: Test the water every 24 hours and wait to see the ammonia reading drop.

7. 7

   Step 7: Add more ammonia to raise the level in the tank back up to the level you chose to start with.

8. 8

   Step 8: Wait until the nitrite level starts to drop

9. 9

   Step 9: (they will be sky high for a few weeks) continuing to add ammonia to feed the bacteria in the tank.

10. 10

    Step 10: When you have 0ppm of ammonia

11. 11

    Step 11: 0 ppm of nitrite

12. 12

    Step 12: and a nitrate reading

13. 13

    Step 13: your tank is ready for fish.

14. 14

    Step 14: Continue adding ammonia until you add your fish.

Detailed Guide

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