It seems to me your nitrites could have been raised by washing the filter sponge in your tank. Not sure since I never heard of anyone doing it. At any rate, it's done and I would keep an eye on your levels for the next few days to be sure there's no spike in ammonia or nitrites.
Best of luck to you!
Hi I did another 50% water change last night and today at lunch time have tested the water!
Ammonia 0
Nitrites 0.3
Nitrates 5
PH 7.5
I also tested the Tap water that had been standing for 24 hours and 0 Ammonia 0 Nitrite and 0 Nitrate
So not quite sure how much water change to do tonight? I am only feeding fish every other day is that ok?
Also brought some Aqauatic Plant Feed yesterday will it be safe to add this to the tank as directed whilst cycling?
Theresa