She is adorable!!! I have a 2yr old so i understand!! Makes anything with fish a bit more difficult... Anyway, heres a quick idea i started using to try & figure out how much water i needed to change when my nitrites went crazy. I started with 50%-only fill test tube up half way & fill the other half with tap (so you have a proper amount to test). Check your nitrites & see what a 50% pwc will do. Then fill with 25% with tank water & 75% tap & check nitrites. Then 10% tank, 90% tap & check nitrites. If you still cant get a readable number, then you have alot wcs ahead of you! Hope this helps!