Originally Posted by SpyderMike
about a week ago was when i was told my nitrites were high and to do a 20% water change
today i went out and bought my own test kit so i can do daily testing w/o having to drive all the way to the store
Good thinking; it pays to have a test kit. Once the tank is cycled, you shouldn't need to worry about ammonia and nitrite; they only cause problems if you overfeed, or fish die and aren't removed, or you add too many fish at once; all of these overload the biological balance. But you should test for pH regularly, as that can fluctuate as the tank matures.
I'm still of the view that partial water changes should only be weekly--but if there are signs the fish are suffering, do a partial water change. You should notice the nitrite lowering and down to 0 within the next few days.
If this is the 37g tank in your photo, there were a lot of fish put in before the tank was cycled. It's probably been hard on them, but if you haven't lost any they are tough.
You want the bacteria to continue to multiply, which they will do to the level that will handle their "food". Don't add any more fish until things are balanced which should be after 8 weeks from setup, and then add few at a time and allow the bacteria to multiply to handle the additional bioload. Don't clean the filter until the tank is biologically established (cycled fully), it won't need it and cleaning the material only kills off the good bacteria. When you do the water changes, gently vacuum the bottom, not into the gravel, as that also removes bacteria you want. When you do finally clean the filter, rinse the material in water from the tank to avoid killing more bacteria than necessary. And always do the filter on a different day from a water change, and don't add new fish for a few days after the filter is rinsed.
I'm assuming this is new to you (fish tanks) so I've tried to make sense of it for you. If the nitrite isn't 0 by mid-week, let us know, but I think it will be. Don't overfeed, that adds to the bioload as well.