Bluelab - Replacement pH Probe – High-Fidelity Sealed Gel-Filled Analytical Electrode with BNC Connection Interface for Guardian Monitors and Combo Meters
Estimated delivery: 5 - 15 Business Days.
+5 days for regional locations on average [More Info]
Bluelab - Replacement pH Probe – High-Fidelity Sealed Gel-Filled Analytical Electrode with BNC Connection Interface for Guardian Monitors and Combo Meters
Restore pinpoint acid-base tracking, eliminate sluggish calibration cycles, and lock in optimal nutrient availability with the Bluelab Replacement pH Probe. Explicitly engineered to survive the high-humidity, chemical-heavy conditions of commercial indoor vertical farms and advanced greenhouse facilities, this professional-grade replacement electrode is the vital diagnostic component that keeps your master analysis gear running at factory-level accuracy. Unlike conductivity sensors, which feature solid metal pins, pH electrodes utilize a delicate, ultra-thin glass sensing bulb filled with a specialized reference gel. Over months of constant contact with concentrated liquid fertilizers, organic additives, and fluctuating water temperatures, this reference gel naturally depletes, and the glass face accumulates microscopic mineral films. This unavoidable material wear slows down sensor response times, causes your calibration settings to drift, and can result in inaccurate readings that lead to major pH crashes or sudden nutrient lockout. This premium replacement probe completely resolves those issues. Featuring a **100% fully waterproof casing certified down to 10 meters (32.8 feet)**, this heavy-duty electrode comes pre-filled with a **low-maintenance, non-refillable reference gel**, keeping it sealed and protected against premature failure. Outfitted with a standard, high-shielding **BNC connection plug**, this industrial-spec probe snaps directly into your existing Bluelab Combo Meter or wall-mounted Guardian Monitor workspace, restoring instantaneous, zero-latency data tracking so your team can make chemical adjustments with absolute confidence.
Best For: Replacing worn, slow-responding, or drifted pH electrodes on Bluelab Combo Meters and wall-mounted Guardian Monitors, restoring crisp 4.01 and 7.01 calibration curves, and maintaining continuous immersion tracking in deep mixing tanks.
Key Features & Technical Advancements
- Universal BNC Connection Interface: Designed with a standard, locking coaxial BNC plug that twists securely onto your Bluelab Combo Meter or Guardian Monitor, providing heavy shielding against electromagnetic field interference.
- 10-Meter Submersible Waterproof Build: Constructed with a rugged, hermetically sealed polymer shell that can be fully submerged down to 10 meters, making it ideal for deep reservoir tanks or drainage pits.
- Maintenance-Free Gel-Filled Core: Pre-filled with a high-purity, non-refillable reference gel that maintains a stable electrical potential over its entire operational life without requiring messy liquid refills.
- Fast-Responding High-Sensitivity Bulb: Outfitted with a specialized glass sensing bulb that reads microscopic hydrogen-ion changes instantly, providing rapid data capture for automated mixing systems.
- Durable, Impact-Resistant Shroud Design: Features built-in structural polymer guard slots around the glass tip, shielding the delicate sensing bulb from physical impact if dropped against tank walls.
- Restores Smooth Calibration Logic: Replacing a sluggish, aging probe eliminates calibration time-outs and errors, allowing your system to lock onto standard reference buffers quickly.
Product Technical Specifications Matrix
| Analytical, Mechanical, & Connection Parameters | Engineering Metric / Design Detail |
|---|---|
| Brand & Equipment Line | Bluelab New Zealand / Commercial Replacement Components Group |
| Primary Hardware Focus | Direct Replacement pH Electrode for Handheld Consoles and Wall Monitors |
| Hardware Compatibility Fit | Bluelab Combo Meter | Bluelab Guardian Monitor (All Generations) |
| Signal Connector Type | Standard Coaxial BNC Plug with Quarter-Turn Twist-Locking Collar |
| Measurement Range Capacity | 0.0 to 14.0 pH (Precision Resolved to 0.1 pH Units on Master Console) |
| Submersion Depth Rating | 100% Fully Waterproof up to 10 Metres Maximum Depth (32.8 Feet) |
| Internal Reference Electrolyte | High-Memory, Saturated Potassium Chloride (KCl) Gel (Non-Refillable) |
| Operating Temperature Tolerance | 0°C to 50°C (32°F to 122°F) Environment / Fluid Compatibility |
| Factory Startup Packaging | Includes Wet-Storage Cap Pre-Filled with Specialized KCl Hydration Solution |
| Manufacturer Warranty Window | 6-Month Factory Replacement Guarantee from Date of Purchase |
Advanced Sensor Maintenance & Substrate Control Tips
- Executing a Flawless Probe Priming and Calibration Sequence: When unboxing your new replacement probe, slide off the plastic storage cap and check the glass bulb—never touch the glass with your fingers, as skin oils can permanently coat the surface and disrupt readings. Rinse the probe tip thoroughly with clean tap water, then submerge it in a cup of fresh 7.01 pH calibration buffer solution. Allow it to sit for two minutes to let the temperature adjust, then press the calibration button on your Guardian or Combo Meter until the display locks in. Rinse the probe again and repeat the process in a 4.01 pH buffer solution to complete the two-point calibration before plunging it into your main nutrient reservoir.
- Root-Zone Hydration and Substrate Coordination: Keeping a fresh, highly responsive pH probe on your equipment rack ensures your automated systems track water chemistry accurately, protecting your root zones from severe acid-induced burn. For optimal root health, accelerated nutrient absorption, and uncompromised drainage, route your perfectly tracked fertilizer recipes into a high-porosity 70/30 blend of Coco Coir and Horticultural Perlite. To ensure completely uniform irrigation delivery across your entire layout, pressurize your feed lines using a heavy-duty Plont PPH Submersible Pump managed by an automated digital shot-timer.
- The Golden Rule of Wet Storage: Preventing Hydration Loss: The absolute fastest way to ruin a brand-new pH probe is to let the glass sensing tip dry out or to store it in the wrong fluid. Storing a pH probe in pure reverse osmosis (RO), distilled, or demineralized water draws out the essential salt ions from the internal reference gel, permanently destroying its electrical calibration. When your meter is not in use, always store the probe tip inside its protective plastic cap filled with official Bluelab pH Probe KCl Storage Solution, or keep it submerged continuously in an active mixing tank.
- De-scaling and Troubleshooting Sluggish Data Readouts: If you notice your monitor's pH readings take several minutes to stabilize or are steadily drifting, the glass bulb is likely covered in an invisible layer of mineral scale or organic biofilm. To resolve this, unmount the probe once a week and clean it gently using an official Bluelab Cleaning Kit. Use a soft-bristled brush dipped in specialized cleaner to break down stubborn calcium deposits on the glass face, then rinse thoroughly. Regular maintenance eliminates reading drift, ensuring your continuous monitoring equipment updates smoothly.
Ideal For (Uses)
- Routine Annual Facility Overhauls: The definitive replacement component choice for commercial greenhouse operators looking to refresh old, worn, or sluggish sensors before starting a new crop cycle.
- Combo Meter Instrumentation Refreshing: Perfect for field technicians who need to restore original, lab-grade performance to a trusted handheld Combo Meter after months of rigorous troubleshooting.
- Guardian Monitor Diagnostics: An exceptional maintenance component for wall-mounted continuous monitoring dashboards that demand a highly durable, fully submersible probe built to handle constant immersion.
Oversized Item Delivery Options
Oversized, heavy, and structural goods ship via specialist freight. Freight is calculated at checkout from estimated packaged volumetric or physical weight. Carrier depot audits may adjust the rate — if the increase exceeds 10%, we will contact you before processing.
Available options include:
✔ Delivery to your closest depot for pickup — default method
✔ Direct delivery — requires an operational forklift on site unless Tailgate Delivery has been specifically requested and quoted (contact us — this cannot be selected at checkout)
✔ Tailgate hydraulic lift delivery — must be specifically requested; contact us for a quote (not available as a checkout option; extra fees apply; required if you do not have a forklift)
✔ Forklift loading at our warehouse (no extra charge if you arrange your own freight)
✔ Direct truck delivery (available in Victoria)
Important Notes:
- Shipping costs vary by location and method
- Any carton or consignment over 25–30kg (or over 200cm) must be palletised
- Without a specifically requested and paid Tailgate Delivery quote, palletised freight requires a forklift on site — otherwise the carrier will redirect to the nearest depot
- Bulky and oversized items cannot be delivered to a PO Box — provide a physical street address
- Failed deliveries, locked gates, unattended sites, or incorrect business/forklift declarations may incur carrier redelivery, demurrage, and restocking fees as set out in our Terms & Conditions
Business Delivery:
- Selecting a business/commercial delivery rate warrants that the address has an operational forklift and certified operator during business hours
- If the carrier cannot unload, the consignment may be redirected to a depot and secondary fees may apply
- Additional fees may apply for failed delivery attempts due to lack of appropriate unloading equipment
See our Terms & Conditions (Article 8) for full freight and delivery rules.
Important Note on Availability & Shipping
Our warehouse is a logistics hub, not a retail showroom. Listing a product online does not mean it is stored at our Thomastown warehouse — many lines ship from supplier hubs (split fulfilment may apply).
How lead times work:
- Product page ETA: The Estimated Time of Arrival (ETA) / lead-time badge shown on the product page at checkout is the agreed delivery timeframe for that order under Australian Consumer Law.
- Metro baselines: Advertised ETAs apply to standard metropolitan zones. Regional and remote addresses may take longer and may attract surcharges.
- Peak seasons: Orders in March–May, August–October, EOFY (June), Black Friday/Cyber Monday (November), and Christmas/New Year (December–January) may automatically add a 2–4 week buffer beyond the product page ETA.
- Supplier-dependent / backordered items: If stock is delayed, we will notify you with a revised ETA. You then have 7 days to accept the new timeframe or cancel for a full refund.
- Adloheat: Custom-made products from Adloheat (Pakenham, VIC) may take 4–12 weeks depending on the order.
Full fulfilment, cancellation, and freight rules are in our Terms & Conditions.
Biosecurity & Interstate Shipping Restrictions
Due to strict state biosecurity regulations, we are unable to ship some products to certain states and territories:
- Potting Mixes cannot be shipped to Western Australia (WA), the Northern Territory (NT), or Tasmania (TAS).
- Seeds cannot be shipped to Western Australia (WA).
Orders placed for these items to restricted states will be cancelled and refunded. It is the customer's responsibility to ensure that the items being ordered can lawfully be delivered to their state or territory.
We Offer the Best Prices
We are committed to offering competitive market rates. If you find an identical, currently stocked product advertised at a lower price by an authorised Australian competitor, contact us before purchase and we will review your request.
Price Match Conditions:
- The competitor must be a registered Australian business (active ABN) with a physical trading address or verified commercial presence in Australia
- The item must be identical in brand, model, SKU, gauge, dimensions, and specifications
- The lower price must be publicly advertised in AUD, currently active, and available for immediate purchase
- Excludes liquidation, clearance, closeouts, damaged goods, and discontinued lines
- Excludes overseas marketplaces and aggregators including Temu, AliExpress, eBay auction sellers, and Amazon third-party sellers
- Excludes trade quotes, bulk discounts, and custom negotiated quotes not publicly visible
- Requests must be made in writing before purchase
How to Request a Price Match:
Email [email protected] with a live link or official quote. We reserve sole discretion to verify and approve price match adjustments. See Article 6.7 of our Terms & Conditions.
Pricing Errors & 105% Store Credit
If a displayed price is incorrect due to a website error or an extraordinary supplier increase, we will contact you before processing. You may proceed at the corrected price, choose an alternative, or cancel for a full cash refund. A 105% store credit may be offered as a courtesy bonus at our sole discretion only. It is not an entitlement, and we may refuse it if we believe it is being abused or sought in bad faith. Full details: Terms & Conditions Article 6.1.
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