Two Ingredients, One Liquid: Meeting the Twins Inside Your Tank
Photo: Christian Giroud, Mariangela de Cesare. Aurélie Berthet, Vincent Varlet, Nicolas Concha-Lozano, and Bernard Favrat, CC BY 4.0, via Wikimedia Commons
Ask most vapers what's in their bottle and you'll get a flavour name and a nicotine strength. Fair enough — but behind every custard, mango or menthol sits a duo doing the heavy lifting: propylene glycol (PG) and vegetable glycerine (VG). At Gemini Vapour we call them the twins, because like any good pair of siblings they're similar, inseparable, and constantly competing for your attention.
So What Are They, Actually?
Both are colourless, odourless food-grade liquids used in everything from baking to medical inhalers. In e-liquid they act as the carriers — the base that holds your nicotine and flavourings and turns them into inhalable vapour.
PG (propylene glycol) is the thinner of the two. It's a flavour solvent, which means it carries taste brilliantly and delivers that satisfying pinch at the back of the throat many ex-smokers chase. It's also the one most commonly blamed for mild sensitivities.
VG (vegetable glycerine) is thicker, slightly sweet, and utterly devoted to vapour production. It's what makes sub-ohm clouds roll across the beer garden. The trade-off? It mutes flavour a touch and doesn't hit the throat nearly as firmly.
The Ratio Is the Recipe
Flip any bottle over and you'll see something like 50/50, 70/30 or Max VG. That number tells you how the twins have been briefed:
| Ratio | Throat Hit | Flavour | Vapour | Best For |
|---|---|---|---|---|
| 50/50 | Strong | Sharp and clear | Modest | Starter kits, pods, MTL |
| 60/40 | Medium | Balanced | Moderate | All-rounders |
| 70/30 | Soft | Slightly muted | Plentiful | Sub-ohm tanks, DTL |
| Max VG | Minimal | Subtle | Enormous | Cloud chasers, PG-sensitive vapers |
A 50/50 in a sub-ohm tank will leak and gurgle — the liquid's too thin for the coil. A 70/30 in a basic pod will wick poorly and taste scorched. Match the ratio to your kit before you match it to your taste buds.
Which Twin Are You Leaning Towards?
There's a simple self-diagnosis. If you find yourself prioritising flavour accuracy — you want your lemon tart to taste like lemon tart — you're a PG-leaning vaper. If you catch yourself watching the mirror after a big exhale, congratulations, VG has you.
Some practical tells:
- Coil life: high-VG liquids gunk coils faster in smaller tanks. If you're replacing coils fortnightly, check your ratio.
- Throat feel: if high-nicotine salts in a 50/50 feel harsh, that's PG doing its job — dial down the strength rather than blaming the flavour.
- Sensitivity: a persistent dry throat or tickle can point to a PG intolerance. Switching to a Max VG shortfill often resolves it.
Shopping Smarter, In-Store and Online
On the British high street, don't be shy about asking the person behind the counter for the ratio — a decent shop will know their range inside out. Supermarket own-brand liquids are nearly always 50/50, which is fine for pods but limiting elsewhere.
Online, shortfills (larger bottles with room for a nicotine shot) are usually 70/30 or higher — ideal if you've moved to a bigger tank. Check whether nicotine shots are included; the UK's TPD rules cap bottled e-liquid at 10ml with nicotine, so shortfills stay nicotine-free until you top them up yourself.
One last tip: keep a small notebook or note on your phone of what you've tried and at what ratio. Palates evolve, and the liquid you loved in a pod might taste completely different in a sub-ohm tank. The twins reward experimentation — and once you know which sibling you favour, you'll never buy blind again.
