New Idea For Fishless Cycling

I have come across an account of how fishless cycling started, and why the method invented then is not applicable today. As I found it on another forum, I won’t link to it but I will summarise it. It was written by a chap who has done a lot of research on the subject.

Fishless cycling was first invented in the late 1990s The method in use in these early days involved adding 5 to 6 drops of ammonia for every 10 American gallons (roughly 37.5 litres). This was imprecise as bottles of ammonia varied in strength.
The next stage was to dose to a particular ppm rather than using a set volume of ammonia. But the people who devised fishless cycling were advanced aquarists. They had heavily planted tanks and always seeded a new tank with media from a mature filter. They chose to dose to 5ppm, an amount of ammonia that was quickly cleared because of their plants and donated media. They did notice that their cycles sometimes stalled and put it down to having added too much ammonia. The two authors who wrote articles on fishless cycling at that time both later revised their methods to use a lot less than 5ppm ammonia.

Then the internet took over from the printed word, and the articles were no longer used. But 5ppm had stuck in everyone’s minds and articles that began to appear on-line recommended this level. The original paper articles that were revised to a lower concentration got lost in the rush to put information out on the internet.
The original level of 5ppm was fine for tanks with a lot of well growing plants and mature media seeding the filter, but fishless cycling was taken up by people who had neither. This is when problems occur with stalled cycles and so on.

At the same time that fishless cycling articles began to appear on-line, Dr Tim Hovanec and his team were researching the species of bacteria that grow in aquariums. Most of the previous research was done on aquaculture and water treatment, both of which have higher levels of ammonia and nitrite. Hovanec’s work showed that the bacteria which grow in aquariums at lower concentrations of ammonia and nitrite are not the same as those which grow at high concentrations.

So now we knew that the bacteria we want in the filter grow at lower levels than at first thought. High levels of ammonia and nitrite impedes then kills them. And at high levels the wrong species grow.
There is usually not a problem with high levels of ammonia. As soon as the aquarist measures a level of 5ppm or over, s/he does a water change to lower it. The problem arises with nitrite. Most test kits only measure low levels of nitrite. Once the reading gets to the top of the scale, it is impossible to know how much nitrite is actually in the water. With the old method, once the ammonia eaters grow and drop the ammonia level to zero, ammonia is added every time the reading drops to zero to stop the bacteria starving, adding to the amount of nitrite in the tank.
It is now becoming evident that these bacteria do not starve. If there is insufficient food, they go dormant. The ammonia eating bacteria do not need to be fed daily. This would allow the nitrite to only rise minimally.

The man on the other forum is suggesting a different way of fishless cycling.
Add 3ppm ammonia and test every other day for ammonia and nitrite
Once the ammonia level drops under 0.75ppm AND nitrite drops below 2ppm, add another 3ppm ammonia and start testing every day.
When the ammonia level drops below 0.25pppm and nitrite below 1ppm, add another 3ppm ammonia.
Repeat this last stage until both ammonia and nitrite read zero 24 hours after adding a dose of ammonia.
Finally do a big water change and get fish.

This method varies in a few ways from the traditional one.
It uses less ammonia, 3ppm instead of 5ppm
Ammonia is only added when nitrite falls low, not every time ammonia drops low
The cycle is finished when both drop to zero in 24 hours, not 12 hours



From what the chap writes, it seems that the reason cycles stall is because so much ammonia is added that the nitrite level gets too high. Rather than my version (where you start with a tiny amount of ammonia, topping up with a tiny amount whenever the reading drops to zero, then increasing the dose when the nitrite reading falls) he says it is safe to add no more ammonia after the first dose until nitrite falls; the ammonia eaters will not starve.



I wish I had read all this before I cycled my betta’s tank, then I could have tested it. Anyone thinking of setting up a new tank……….?

That would test this new idea nicely if you are willing. If I'd read about this earler this year, I'd have tried it with my 25 litre tank.

The chap is saying that the ammonia eaters don't starve as quickly as we used to think; they can go quite a while without food. That's why he is suggesting that the second dose of ammonia is only added after the nitrite level falls, while the original method says to dose as soon as only ammonia falls.
Our test kits only measure up to about 5pppm nitrite. The kits show 5ppm no matter how high the level actually is, so we don't know how high nitrite really is. And a high nitrite stalls the cycle. The chap's method keeps nitrite low so the cycle should go faster. He suggests that most cycles will only need 3 doses of ammonia to complete - the first one, then 2 more after nitrite falls.

Very interesting, and if I do another cycle, I'll try it. Unfortunately it doesn't give me a clue as to my current fishless cycling predicament http://www.thinkfish.co.uk/forum/index.php/topic,445.msg5046.html#msg5046

I started off following your how-to, with a few twitches, and now its gone a bit odd.

Do the nitrite eaters starve fast - if so mine could get in trouble?

Hey,

I started cycling my tank earlier in the week using this method, it reached stage 4 today. The ammonia was 0.25ppm and the nitrite was about 3ppm, so I've added my full dose. 

I think my ammonia was weaker than yours as I needed 6.5ml for 150l-ish of water to reach 3ppm of ammonia. Also, even with the heater on maximum, I can't get the water any warmer than about 30^oC. Is that okay?

Tasha 

Hey,

Readings for ammonia on 29th and 31st both showed zero ammonia, so I added the maintenance dose of 2.17ml last night. I will test later and let you know the results.

Tasha

Hi Tasha

Looks like your cycle in progressing nicely, will be interedtibg to see how quickly it finishes too!

Coming along nicely! Keep patient 

Hey,

Of course I'll do a summary Sue if it will help Tonight's ammonia and nitrite levels are both reading 0ppm so once again I've added the full dose of ammonia and we'll se what tomorrow brings.

I know I need to be patient but I've been browsing through the gallery threads looking at everybody's tanks and it's making it difficult to be! 

I need to work out how I'm going to scape my tank, where shall I post questions about that?

Tasha 

You might want to put the kettle on and settle down with a brew and look through this to get some ideas of what's possible.

Your Nitrate is high because that's not being removed from your water, it's always being added to by the oxidation of Nitrite by your bacteria. Your Nitrites fluctuate 'cos one set of bacteria are making them from Ammonia, and a different set of bacteria are using them up. It sounds like you're almost finished with your cycling but you'll really should wait for back-up on this as cycling isn't my 'thing'. The Nitrates get removed with a huge pre-fish water change so don't worry about them.