NitrIte and NitrAte
PH
Ammonia
Avoid testing strips as they can be inaccurate, try to get ones that use the test tubes. They normally cost £5 to £10, for each, in the UK, (about $10-$20)
If it's a newly set up tank, you should test everyday so that you can keep track of the nitrogen cycle, and then go down to once a week once you have cycled your tank.
If you need more information on cycling your tank, look here: http://fins.actwin.com/mirror/begin-cycl... http://fins.actwin.com/mirror/begin-cycl...