---
product_id: 32105900
title: "pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each)"
brand: "bluelab"
price: "€ 63.56"
currency: EUR
in_stock: true
reviews_count: 8
category: "Bluelab"
url: https://www.desertcart.ie/products/32105900-ph-4-0-and-7-0-calibration-solution-kit-ph
store_origin: IE
region: Ireland
---

# Long shelf life, ready-to-use Dual pH 4.0 & 7.0 calibration NIST traceable precision pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each)

**Brand:** bluelab
**Price:** € 63.56
**Availability:** ✅ In Stock

## Summary

> 🌿 Calibrate like a pro, grow like a legend.

## Quick Answers

- **What is this?** pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each) by bluelab
- **How much does it cost?** € 63.56 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.ie](https://www.desertcart.ie/products/32105900-ph-4-0-and-7-0-calibration-solution-kit-ph)

## Best For

- bluelab enthusiasts

## Why This Product

- Trusted bluelab brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Dual Calibration Power:** Includes both pH 4.0 and 7.0 solutions to cover a wide range of calibration needs for hydroponics, aquariums, and more.
- • **Precision You Can Trust:** NIST traceable solutions ensure your pH meter delivers lab-grade accuracy every time.
- • **Extend Your Meter’s Lifespan:** Regular calibration maintains peak performance and longevity of your pH pen or meter.
- • **Effortless & Ready When You Are:** Pre-mixed, ready-to-use solutions save time and reduce hassle—no mixing required.
- • **Optimize Your Grow with Confidence:** Accurate pH readings mean healthier plants and better yields in your garden or grow tent.

## Overview

The Bluelab pH 4.0 & 7.0 Calibration Solution Kit offers NIST traceable, dual-buffer solutions designed to maintain the accuracy and longevity of your pH meters. Perfect for hydroponics, gardening, and aquatic environments, these ready-to-use 500 ml bottles ensure reliable, hassle-free calibration that keeps your nutrient solutions perfectly balanced for optimal plant health.

## Description

Bluelab pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each): desertcart.com: Industrial & Scientific

Review: Perfect - I followed the directions to the letter and the calibration solutions worked perfectly. I feel so much better about my grow knowing the reading I am getting are true readings. The solution hand my Blue Labs OnePen with perfectly calibrated and fast results
Review: Works Well - I own the blue lab ph pen and EC meter, and these solutions are perfect for calibration of the pH pen. I bought large bottles, still working super well a year later, probably have enough to last me another 3 years of regular monthly calibration checks/calibrations. Between the nice test pen and these solutions my hydroponic results have improved. Good stuff.

## Features

- Ensures accurate readings - Our pH calibration solution helps maintain the accuracy and reliability of a pH pen, probe, or tester. Calibration ensures accurate readings. This helps keep the pH level in check for the health of plants, swimmers, or aquatic life.
- NIST Traceable - Our pH calibration solutions are NIST traceable and meet the highest quality standards. This set includes two crucial pH levels, pH 4 and pH 7, allowing you to calibrate a wide range of pH instruments.
- Improves the longevity of the pH pen or tester - Regular calibration helps extend the life of your pH meters by maintaining their performance. Useful for providing accurate pH in hydroponics, aquariums, swimming pools, or gardens.
- Easy-to-use and long shelf life - Our electrolyte solutions are ready-to-use right out of the bottle, saving you time and effort. Our pH calibration solutions don't need frequent replacements as they have a long shelf life.
- How to calibrate - Make sure your pH pen or probe is clean and hydrated. Turn it on. Place the probe tip in a fresh pH 7.0 calibration solution. Rinse the pen or probe tip in clean tap water and shake off the excess. Calibrate to pH 4. A calibration confirmation will appear to show a successful calibration. Recalibrate if the symbol disappears.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B01GQVSQGG |
| Best Sellers Rank | #15,711 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #18 in Lab pH Meters |
| Date First Available | June 7, 2016 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 2.27 pounds |
| Item model number | BL-COMBO-1 |
| Manufacturer | bluelab |
| Package Dimensions | 7.01 x 6.02 x 2.83 inches |

## Product Details

- **Brand:** Bluelab
- **Item Form:** Liquid
- **Item Volume:** 500 Milliliters
- **Molecular weight:** 32.06
- **Package Information:** Bottle

## Images

![pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each) - Image 1](https://m.media-amazon.com/images/I/71+ybs4c1zL.jpg)

## Questions & Answers

**Q: Can you reuse solutions?**
A: Yes a couple of times but I wouldn’t pour it back in the bottle if you’ve used it already. For example I have 3 ph meters so I’ll put some of each in a cup and use the same solution to calibrate all 3 of my ph meters then toss the solution. The bottles last a long time though.

**Q: The bottle doesn’t specify how much solution to add to how much water to make the ph 7.0 and 4.0 solutions. It just says add the required amount???**
A: You don't add anything its pre made to the ph level.

**Q: Can i use this solution for other brand ph meters ? i own a adwa ph meter, or is this only for bluelab products ?**
A: It will work for all PH meters.

**Q: How often would I expect to run out of solution? I would hope for $45.00 this would last a t least a year.**
A: I believe it will last a year I Calibrate my pen whenever it goes out of calibration which is usually about once a month

## Customer Reviews

### ⭐⭐⭐⭐⭐ Perfect
*by M***J on October 25, 2024*

I followed the directions to the letter and the calibration solutions worked perfectly. I feel so much better about my grow knowing the reading I am getting are true readings. The solution hand my Blue Labs OnePen with perfectly calibrated and fast results

### ⭐⭐⭐⭐⭐ Works Well
*by R***A on July 21, 2023*

I own the blue lab ph pen and EC meter, and these solutions are perfect for calibration of the pH pen. I bought large bottles, still working super well a year later, probably have enough to last me another 3 years of regular monthly calibration checks/calibrations. Between the nice test pen and these solutions my hydroponic results have improved. Good stuff.

### ⭐⭐⭐⭐⭐ Fast delivery, quality products
*by M***G on April 9, 2025*

Fast delivery, quality products

## Frequently Bought Together

- Bluelab pH 4.0 & 7.0 Calibration Solution Kit - pH Meter & pH Pen Calibration for Balanced Nutrient Solution NIST Traceable | Hydroponics, Gardening & Growing Tents (500 ml/ 16.9 Fl Oz Each)
- Bluelab STSOL120 KCL Storage Solution 120ml pH Probe and Pen, Maintain Meters Used for Water, Soil, and Hydroponic System or Indoor Plant Grow White

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*Product available on Desertcart Ireland*
*Store origin: IE*
*Last updated: 2026-02-04*