Is it possible a tank can fail to cycle?

Hi,

I have 2 tanks running 1 is 6x2x2 and the other is 2.5x2x1 and both have cloudy water.

The 6x2x2 is running a 2260, and a 2080 (currently broken but the bio media is in the flow of the water in the tank. When i test with the kits the ammonia is reading, on the 6x2x2 the liquid test is at about 8ppm the seachem ammonia alert in the tank is reading 0.02ppm (Safe) nitrate is 0 and nitrite 2ppm


The smaller tank is running a classic 2217 the ammonia is 0,25ppm, nitrate and nitrite is zero.

the tanks have been running for a months and the cloudyness is not subsiding

E.C. said:

Do you perform WC on it? Or maybe it's because of the substrate? Pics pls.

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both tanks are bare bottom, I did a water change a few days ago, but it has been like this for about 2 months, constantly milky water

js302 said:

hi
Could anything be killing your bacteria ?
Did you clean the tank with bleach or anything?
Are you w/c-ing with chlorinated water – surefire way to kill your bacteria.
You must have no uv filtration - which I don’t think you do.
Can you get some filter media from a friend ??

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My cycle broke down about 3 months ago, for some reason and has never recovered, I have UV but it is off.


I usually run a 2262 and a 2080, but the 2080 is currently out of action with a broken head....

deeda said:

If the ammonia is actually 8 ppm you need to bring it down to at least 3 ppm. The high ammonia is stalling your cycle.


What are you using to cycle the tanks?

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like i said above my tank is already populated with fish, and cycle crashed for some reason months ago and it has never recovered.


In the 6x2x2 i have 3 30cm+ americans in there and 6 20cm americans in there also. I have nowhere to house the fish while the cycle fixes up
in the smaller tank there is 2 hoplo catfish 6cm each, 2 bristlenose about 5cm each and 1 zonatus about 6cm

David R said:

What are you using to provide ammonia for the cycle?


What is the temp?


What kind of test kits are you using and have you double-checked the readings with another test? I know I would struggle to get as accurate a reading as 0.02ppm with my liquid API test kit.

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as above, the cycle crashed on a populated tank and i have big fish.


the temp is 25 degrees on both tanks, I have double ceacked with another liquid kit and they are the same, i get the 0.02ppm reading from the Seachem Ammonia Alert disk that sits in the tank, it shows a "Yellow" colour that means "Safe"


I am unsure of what to do....my cycle crashed because my house is on rain water, my wife didnt tell me the tank was emptied and that she refilled it with town water which has chlorine and chloramine, I did an 80% water change with no Prime and everything collapsed.


now when i water change i turn off my canister for 10-15 mins while i add the new water and allow the Prime to mix through..


Should i do more water changes?