It's eating a lot of live tubifex so doing 50% WCs every day now (the bio filter is not working because I had used acriflavine to quarantine the fish), what i normally do in other tanks is adding water from the municipal water supply and adding de chlorinator crystals (sodium thiosulfate) directly before new water is added. **** But in this one's tank I'm keeping water in a 50L bucket overnight and using it, its a hassle in few days I'm gonna do the same method which I do for water changes in other tanks to this one also.