I think my cycle has crashed

[The_Labyrinth]

I agree if one is unable to give time to time.

That's it. I should have specified "using RO water".

Exactly, the 'source' of the water needs to change to do effective water changes.... adding not-so-great water during your water changes introduces other problems which is not always a good solution, better to give the existing water time to process at that point.

 

[Avel1896]

It is so obvious to me I forgot to mention ROwater !