Bit of an update here and more info. I'll share how I've been dealing with the issue so far and hope one of you might have a better way. It seems to happen with sweeter juices. I have a fruity COPYRIGHTDMCA juice it happens with, basically if I clean my tank completely, put a clean coil in and fill it, the juice stays it's same color. However, when it gets low and I refill it, it begins to discolor. I just got a new juice- vanilla carmel coffee that the same thing happens with. First tank is normal, if I refill it without cleaning it and changing the coil it changes darker. Also, this does seem to effect the vapes. I don't get as much of a hit (vapor or flavor) when this happens. Like I said, what seems to fix it is taking the tank apart, cleaning the whole thing and changing the coil. That's kind of a pain to do every time I empty a 2.5 ml, but I guess I'll do it if I have to. Would simply rinsing the coil off and letting it dry be sufficient cleaning do you think? I've been rinsing mine for like 5 minutes at a time, letting them soak for 2 hours, dry burning them, rinsing them again and letting them dry again. Seems a bit much to do with every tank. Also, the Kanger Aerotank V2, is it safe to get every part of that wet? I have not been rinsing the part the coil screws into (sorry I don't know the name), but rinse every other part. Sorry this is kind of rambling.