Water changes during cycling

Hello everyone,

As you may have read on a earlier post, i mistakenly thought my tank was cycled .

However i am now in the process of cycling the tank correctly, but i have noticed that the water is looking pretty disgusting and starting to smell pretty bad. So I have a few questions to people who have successfully cycled a tank before.

During cycling a tank, should you be doing water changes and how often?
How long should you leave ammonia causing objects (such as poo and bits of food) in the tank before taking them out ad replacing them?

Moony

Hello Moony,

You do not need to perform any water changes during the cycling process. However, if you have a high ammonia reading then you can do a partial water change because the high ammonia reading can hinder the cycling process. You will also have to perfrom partial water changes towards the end of the cycle (i.e. when nitrate has evolved) because this is the most common method for exporting nitrate.

The stagnant smell is most likely because your tank has too much dissolved organic matter. Also, if you have sand as your substrate, give that a stir through because anaerobic pockets can form within the sand thus resulting in the release of hydrogen sulfide gas. Hydrogen sulfide gas is that rotten eggs smell. Funky stuff.

If the bits of food/poop are starting to form a mold on them, remove them. Remember that you do not require that much ammonia to kick-start the nitrification cycle.

Jay.

Hey Jay thanks for the reply,

Kal El said:

If the bits of food/poop are starting to form a mold on them, remove them. Remember that you do not require that much ammonia to kick-start the nitrification cycle.

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I took out the organic matter in the tank because it was moldy, then tested my ammonia level which was still about 3-4mg/l.

So correct me if I'm wrong...but the only time i will put fresh organic matter in the tank now, is when i get a rise in nitrite levels?

Moony

...but the only time i will put fresh organic matter in the tank now, is when i get a rise in nitrite levels?

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Correct. However, if the ammonia level does not drop after some time then you can perform a partial water change to lower it. An ammonia reading of 3-4 mg/L is rather high. But at least you know that you've got enough ammonia in the tank to sustain the nitrifying bacteria.

Jay.

I am not aware of your other thread right now, but surely you do not have any animals in the tank?

Nope.. definitely no animals in there!

I have a baby axolotl (about 9cm) waiting to go into the tank after it is cycled, but thanks for the concern. I know if anything were in there, they would live a short and cruel existence.

Moony