damn nitrite

[fish&chips]

lo all i think i got a problem but maybe not

i tested for nitrite 2 days ago and it seemd to be almost clear and at 0
then yesterday i needed water change
so i looked at the filter to clean it (real mess
and found 1 the filter bags with carbon in has split (was old )
so i replaced it i had 2
and cleand the rest of the filter

as my filter was maturing could this be the reason nitrite seems worse

its a interpet test and says if turns pink slight nitrite (2 days ago ALMOST CLEAR SEE THRU

it now whent dark pink when i thought it would be clear changing the filter and cleaning it ...is this the problem
can i buy somthng to help bring the nitrite down

ph is 7.5 i cant get that better watter smells like fresh earth (told this is very good

could the water change alone put the ph up and with the filter

 

[CFC]

How long have you had the tank set up and how did you rinse the filter media ?
Have you been testing for ammonia too, what are the ammonia readings ?
The pH will stay at whatever level it comes out of the tap at unless you have something in the tank that changes it (bogwood/peat to bring it down or crushed coral to bring it up).