Ammonia - 0ppm
Nitrite - 0.25ppm
Nitrate - 15ppm
I'm about to do a water change, and it isn't the nitrite causing the molly's colour change because it has been 0ppm the last two weeks when I checked and that's when its colour changed.
I don't have a pH testing kit, but my water is hard, so it's probably slightly alkaline.
Tank is 30 gallons, there are 3 mollies, 1 platy, 8 neons, 1 glowlight, 5 red-eye tetras and 2 kuhli loaches.