Mixing longfills might sound intimidating initially, but it's genuinely straightforward—even for complete beginners. The process requires no specialised equipment or technical expertise, just a few simple steps and minimal ingredients. Here's everything you need to know to create your perfect customised vape juice.

Essential Ingredients

• Your chosen longfill bottle (containing concentrated flavour)
• Nicotine shots (10ml bottles typically containing 18mg nicotine)
• VG/PG base liquid (optional, depending on desired final strength and ratio)

Step-by-Step Mixing Process

1. Calculate your requirements: Determine how much nicotine and base liquid you'll need. Most longfill bottles include mixing instructions on the label, showing recommended additions for different final strengths (typically 3mg, 6mg, or 12mg).
2. Add nicotine shots: Carefully pour your nic shots into the longfill bottle. For example, adding two 18mg nicotine shots to a 60ml bottle (20ml concentrate + 40ml total additions) creates approximately 6mg final strength.
3. Add base liquid: If you're not filling the bottle completely with nicotine shots, top up with your preferred VG/PG base. This allows you to achieve both your desired nicotine level and VG/PG ratio. Want massive clouds? Opt for high-VG base. Prefer stronger throat hit? Choose higher-PG options.
4. Shake thoroughly: Secure the cap tightly and shake vigorously for 2-3 minutes. This ensures all components blend completely, distributing flavour and nicotine evenly throughout the mixture.
5. Test and adjust: Some flavours are shake-and-vape ready, meaning they're immediately enjoyable. Others benefit from steeping (more on this below). Take a small test before committing, and remember—you can always adjust future mixes based on this batch's results.

The mixing process genuinely takes just minutes, yet it unlocks tremendous potential for personalisation. As you become more comfortable, you'll develop instincts about what works best for your palate and equipment, potentially even experimenting with combining different flavour concentrates for unique blends unavailable anywhere else.

The true magic of longfills emerges when you start exploring customisation possibilities. Unlike pre-mixed bottles where you're locked into someone else's decisions, longfills position you as the master blender, capable of creating vape juice that matches your exact requirements.

Nicotine Strength Customisation

One of the most significant advantages involves nicotine control. Perhaps you're gradually reducing intake as part of a journey towards nicotine-free vaping—longfills accommodate this perfectly. Start with 12mg, then move to 6mg, then 3mg, and eventually 0mg, all using the same flavour base you've grown to love. You're not forced to find new favourite flavours at each strength level; your preferred taste evolves with you.

Standard mixing typically creates these common strengths:

• 0mg (nicotine-free): Simply add VG/PG base without any nic shots—perfect for cloud chasers or those who've completed their nicotine journey
• 3mg (low strength): Ideal for casual vapers or those using high-powered sub-ohm devices where nicotine delivery is more efficient
• 6mg (medium strength): The sweet spot for many, providing satisfying nicotine delivery without overwhelming throat hit
• 12mg+ (higher strength): Suited for MTL devices or recent switchers from traditional cigarettes who need stronger nicotine satisfaction

VG/PG Ratio Mastery

Understanding VG/PG ratios transforms your vaping experience. These two base liquids serve different purposes, and manipulating their balance allows you to optimise performance:

Vegetable Glycerin (VG): This thicker, sweeter liquid excels at vapour production. High-VG mixes (70/30 or 80/20 VG/PG) create dense, satisfying clouds and deliver smoother throat sensation. They're ideal for sub-ohm vaping and devices with large airflow. However, high-VG liquids can be slightly harder on coils and may mute complex flavour notes.

Propylene Glycol (PG): Thinner and flavour-carrying, PG delivers that characteristic throat hit beloved by former smokers. Higher-PG ratios (50/50 or 40/60 VG/PG) work beautifully in MTL devices, pod systems, and lower-powered equipment. They provide intense flavour clarity and that satisfying throat sensation, though with reduced vapour production.

Popular ratios include:

• 70/30 VG/PG: The modern standard for sub-ohm vaping, balancing excellent vapour production with acceptable flavour delivery
• 60/40 VG/PG: Versatile middle ground working across various device types
• 50/50 VG/PG: Classic balanced ratio, perfect for MTL devices and pod systems

Both longfills and shortfills occupy important spaces in the modern vaping landscape, each serving different needs and preferences. Understanding their distinctions helps you make informed choices about which format suits your situation best.

When to Choose Longfills

Longfills excel when you prioritise value, flexibility, and involvement. They're particularly suited for:

• Regular vapers who go through significant quantities of e-liquid monthly
• Enthusiasts who enjoy the DIY aspect and want deeper engagement with their hobby
• Those using multiple devices with different optimal VG/PG requirements
• Vapers gradually adjusting nicotine levels as part of reduction journeys
• Anyone seeking maximum value from their vaping budget

When to Choose Shortfills

Shortfills work better when convenience takes priority:

• New vapers still learning preferences and not ready for mixing decisions
• Those wanting minimal preparation time before vaping
• Casual users who don't consume enough to justify bulk mixing
• Situations where you want guaranteed consistency without variables

Importantly, these aren't mutually exclusive choices. Many experienced vapers maintain both formats in their collection—shortfills for convenience and immediate variety, longfills for their everyday favourites where value and customisation matter most.

Steeping—allowing your mixed e-liquid to rest and mature—represents one of the most significant yet often overlooked aspects of working with longfills. Whilst some concentrates perform beautifully straight after mixing (shake-and-vape), many develop substantially richer, more cohesive flavours through proper steeping. Understanding this process elevates your results from good to exceptional.

Why Steeping Matters

Think of steeping like aging wine or marinating meat—it's about allowing time for chemical processes to occur naturally. When you combine flavour concentrates with base liquids and nicotine, these components need time to fully integrate. Complex molecules bond, harsh edges mellow, and subtle notes emerge that were hidden immediately after mixing. The result? Smoother, fuller, more satisfying flavour.

Flavour Types and Steeping Requirements

• Fruit flavours (1-3 days): Simple fruit profiles often shine quickly, though a brief steep enhances natural sweetness and rounds sharp edges. Citrus especially benefits from short resting periods.
• Menthol/Ice (0-2 days): Generally shake-and-vape friendly, though slight resting allows cooling agents to distribute evenly throughout the liquid.
• Desserts/Bakery (1-2 weeks): These complex profiles demand patience. Custards, creams, and cake flavours transform dramatically during steeping, developing richness and eliminating any artificial notes present immediately after mixing.
• Tobacco (1-3 weeks): Perhaps the most steep-dependent category, tobacco concentrates mature substantially over time, developing authentic depth and eliminating harshness.
• Beverages (3-7 days): Coffee, cola, and similar profiles benefit from moderate steeping, allowing layered notes to emerge and integrate.

Steeping Methods

Natural steeping (recommended): Simply store your mixed bottles in a cool, dark cupboard away from direct sunlight. Shake gently once daily to encourage mixing. This patient approach delivers the best results, allowing flavours to develop naturally without stress from heat or excessive agitation.

Warm water bath (faster option): If you're impatient, placing your sealed bottle in warm (not hot) water for 30-60 minutes can accelerate initial integration. However, this doesn't replace natural steeping entirely—it simply jumpstarts the process.

Patience with steeping genuinely rewards you with superior vaping experiences. That same longfill which tastes merely "okay" immediately after mixing might become your absolute favourite after proper maturation. It's worth investing the time to discover each concentrate's full potential.

Selecting appropriate nicotine strength significantly impacts both satisfaction and enjoyment. Too high creates harsh throat hit and potential discomfort; too low leaves you unsatisfied and vaping excessively. Finding your sweet spot involves considering several factors, and longfills' flexibility makes experimentation straightforward.

Factors Influencing Strength Choice

Device type and power: Sub-ohm devices operating at higher wattages deliver nicotine very efficiently, meaning lower strengths (3mg or 6mg) suffice. Conversely, lower-powered MTL devices and pod systems benefit from higher strengths (6mg, 12mg, or even 18mg) to provide equivalent satisfaction from smaller vapour volumes.

Previous smoking habits: Recent switchers from traditional cigarettes often require higher nicotine initially, gradually reducing as vaping becomes established. Someone who smoked 20+ daily might start with 12-18mg, whilst lighter smokers find 6-9mg appropriate. Over time, many naturally reduce strength as their bodies adjust.

Vaping frequency and duration: All-day vapers typically prefer lower strengths to avoid excessive nicotine intake, whilst occasional users might choose moderate-to-high strengths for quick satisfaction during shorter sessions.

Practical Strength Guidelines

• 0mg (nicotine-free): Perfect for those who've eliminated nicotine dependency but enjoy vaping's sensory aspects, or cloud enthusiasts prioritising vapour over nicotine delivery.
• 3mg: The choice of experienced sub-ohm users and those maintaining minimal nicotine intake. Provides subtle satisfaction without dominating the experience.
• 6mg: Versatile middle ground working across device types. Popular amongst former moderate smokers and those seeking balanced nicotine delivery.
• 12mg: Suited for MTL devices and recent switchers needing stronger throat hit. Delivers substantial nicotine satisfaction from modest vapour production.
• 18mg+: Reserved for specific situations—very high-resistance MTL devices, extremely light vapers, or those with particularly high nicotine requirements. Use cautiously to avoid over-delivery.

Adjustment and Fine-Tuning

Longfills empower gradual strength adjustment. If 6mg feels slightly strong, your next mix could combine one nic shot with extra base liquid for approximately 4.5mg. Want something between 3mg and 6mg? Split the difference. This granular control enables precise personalisation impossible with pre-mixed options.

Monitor how you feel throughout the day. Symptoms like light-headedness, nausea, or jitteriness suggest excessive nicotine—reduce your strength. Conversely, if you're vaping constantly without satisfaction or experiencing cravings, slightly increasing strength might provide better results whilst actually reducing overall consumption.

Whilst quality and customisation draw many vapers to longfills initially, the substantial cost savings often cement them as permanent favourites. Understanding the economics reveals just how much value these concentrated formats deliver compared to traditional alternatives.

Cost Breakdown Analysis

Consider a typical scenario: A 60ml longfill bottle containing 20ml concentrate costs approximately £10-15. Adding two nicotine shots (£2-3) and VG/PG base (£2-3 for 40ml) brings your total investment to roughly £14-21 for 60ml of premium, customised vape juice. That's approximately £0.23-£0.35 per ml.

Compare this to purchasing six 10ml bottles of premium e-liquid at £4-5 each (£24-30 total) for the same 60ml quantity—that's £0.40-£0.50 per ml. The savings become even more pronounced with 120ml longfills, where economy of scale further reduces per-ml costs.

For someone consuming 10ml daily (a moderate vaping rate), monthly savings switching to longfills could reach £30-50—that's £360-600 annually. Over a year, these savings fund significant upgrades to devices, extensive flavour exploration, or simply reduce vaping's impact on your budget.

Additional Value Considerations

• Reduced waste: Fewer individual bottles means less packaging waste and fewer disposal concerns—environmentally conscious vapers appreciate this sustainability aspect.
• Bulk purchasing benefits: Many retailers (including VapeBus) offer multibuys and bundle deals on longfills, stacking additional savings atop already economical pricing.
• Flexibility reduces waste: Unlike pre-mixed bottles where you're committed to the entire quantity regardless of enjoyment, longfills can be mixed in smaller test batches. Discovered you don't love a particular flavour? You haven't wasted a full 60ml—just remix the remaining concentrate differently.
• Learning transfers value: Knowledge and experience gained mixing longfills empowers you across all vaping aspects. Understanding VG/PG ratios, nicotine calculations, and flavour profiles enhances every future purchase decision.

Maximising Your Investment

Strategic purchasing amplifies savings further. Stock up during sales on flavour concentrates (which have excellent shelf life when properly stored), buy nicotine shots and base liquids in larger quantities, and take advantage of bundle offers. Planning ahead transforms already excellent value into extraordinary economy.

Remember: cheaper doesn't mean compromised quality. You're paying less because you're handling simple mixing yourself rather than paying for manufacturing convenience. The actual flavour concentrate quality matches or exceeds what's in premium pre-mixed lines—you're just cutting out the middleman services you don't need.

Investing in quality longfills deserves protection through proper storage practices. Correct handling preserves flavour integrity, maintains nicotine potency, and ensures safety—extending your concentrates' usable life significantly.

Essential Storage Guidelines

• Cool, dark locations: Store bottles away from direct sunlight and heat sources. UV light and elevated temperatures degrade both flavour compounds and nicotine, causing quality deterioration. A cupboard, drawer, or dedicated storage box works perfectly.
• Upright positioning: Keep bottles standing upright to prevent prolonged contact between liquid and cap seals, which can cause degradation over time.
• Secure sealing: Always ensure caps are tightly closed. Exposure to air oxidises nicotine (causing peppery harshness) and allows flavour volatiles to escape.
• Temperature consistency: Avoid locations experiencing significant temperature fluctuations. Consistent, moderate temperatures (15-20°C) preserve quality optimally.
• Child and pet safety: Store all vaping products securely out of reach. Concentrated nicotine poses serious risks if accidentally ingested, and even nicotine-free concentrates should be kept safely.

Shelf Life Expectations

Properly stored, unopened longfill concentrates remain viable for 12-24 months. After opening, quality persists for 6-12 months, though most vapers consume bottles well before degradation becomes noticeable. Mixed bottles containing nicotine should ideally be used within 3-6 months for optimal experience.

Signs of Degradation

Occasionally check stored liquids for quality indicators. Nicotine oxidation causes colour darkening (clear or light liquids turning amber or brown)—this doesn't necessarily mean unsafe, but flavour and throat hit may be affected. Separation of components (visible layers) simply requires vigorous shaking to re-homogenise. However, any off-putting odours or unusual sediment warrant caution—when in doubt, it's safer to replace questionable stock.