I use test strips and always right where they are suppost to be, but I have just talked to LFS and thought it would be a good idea to start feeding just once a day instead of twice and to bump up temp from78 to 82 degrees
I think that many of us tend to over filter our tanks compared to what the manufacturer's recommend regarding the rating on their filters.
Do you have an aquarium test kit so you can share what your ammonia, nitrite and nitrate levels are for your tank? Fin rot may be a result of poor water quality or maybe some aggression among your fish that caused some injury.