good to see another MTS newbie here. would love to know what u see in your oscar, everytime i see them at LFS
they freak me out. think i may be a small fish person.:P As for the water testing, ever since i bought a master test kit, i have been more paranoid then ever. i really believe that your fish will tell you if anything is not quite right.
what sort of cory do you have, i thought about getting some for my 200 litre tank, currently only have kuhli loaches in there, but not sure how big the corys grow.