I've used these - I must say that for me, they worked, I tested the water after 24 hours and it had perfect levels..... have you got fish in your tank?
Unlike bio-spira, Bactinettes conatins the wrong bacteria for nitrite oxidisation.thankyou it does work, like bio spira (US) it has to be kept refridgerated (to make sure the bacteria stay alive) but it does work.