Why Is Juice Turning Dark In Tank?

Why has the juice in my tank getting dark and the cotton on my coil getting dark as well? I really haven’t done anything different except to purchase my VG from another supplier. The mix I’ve been using is mainly VG, no PG other than the concentrate. I mix for a buddy of mine to and his has been doing the same thing lately? I’m new to the page and the forum, so I hope I’m asking in the right place!

Perhaps the sweetener in the flavorings themselves is caramelizing on the coils. Quite a few flavorings have some type of sweetener in them.


Could be I guess. All I use in my buddies is FW Tutti Fruitti, VG and 3mg
The other one that is doing it is: Monkey Fart, Banana, and Banana Cream, VG and 1.5mg

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Some FW flavorings contain corn syrup or sugar, while i do not see TF on the list it doesnt mean that there is none in it as the list is incomplete.


If the only thing you have changed is the VG source, and it wasnt changing with the old vg, than perhaps that VG has something in it that is reacting to the flavors and or with the heat? what VG are you using now? and before?

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Using BullCity now and was using NicVape before

the other thing I have noticed with some juice is it tends to darken naturally on its own anyway, as it ages/steeps, so maybe with it being in heat would also cause it to sort of speed that process along… tho i am inclined to think like ken said, if it has sugars that are carmelizing on the coil, those now-burnt particles can mix back with the juice and also darken it… are you using new coils/wicking? i would think if the wicking is being burnt, can also probably darken liquid it is in, too… shots in the dark here, man, hard to say when there is so many factors in play

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Also…what mod and tank are you using?

As connected to the coils getting older I used to have that happen to when I used aspire products, especially on their bvc oils. It became the warning sign the coil was about to go out.


New coil. I’m not sure. Guess I’ll start with the flavoring idea. The VG is coming from a reputable source, right?

Its my wifes KangerTech Nano with their 0.5 coils

BullCity is a very well known vendor of good VG so far. Yup.


The test for the coil issue is just put clean and clear liquid it. If it’s the coil you’ll see it coming through the ports on the premade coil.

From there it may just be a combo of the juice your mixing and an older coil.

As for what I use now, uwell crown tank, the coil will be guncked up and drop in flavoring. I don’t get the reverse leakage of colored fluid. Sure there is some that goes back. But it’s not the same. The aspire coils were good but I’d only get a week of usage. The crown coil I get a month.


That’s good to know because they’re about the only place I order from right now. Thanks Alisa!

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Also touched upon here:

In short: Liquid comes in contact with coil gunk, and due to the way tanks work (vacuum), some juice from the coils gets sucked back in the tank…

I am a bit puzzled by this as he said he was using a fresh coil… perhaps he is going too hot, so burning it quickly?

That’s my guess at least - It could be a coil-gunking juice :slight_smile:

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