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Spider Farmer 5-in-1 pH, EC and TDS Meter for Hydroponics
£35.00
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Spider Farmer 5-in-1 pH, EC and TDS Meter for Hydroponics
£35.00
The Spider Farmer 5-in-1 is a pH meter for hydroponics that also reads EC, TDS, water temperature and salt, all from one waterproof pen. Dip, wait a few seconds, and you know exactly what your plants are drinking.
It is the friendliest way to look after a hydroponic garden, a bucket of tomatoes or a tank of rainwater, and children love being the official water scientist.
A pH meter for hydroponics that reads five things at once
The backlit screen shows pH and TDS side by side, so you can check acidity and feed strength together. Automatic temperature compensation keeps readings honest whether the water is cool or warm.
It charges by USB-C, so there are no fiddly batteries, and one charge lasts for months of occasional checks.
What you can test with it
- The water in a countertop hydroponic garden or DWC bucket
- Tap water and rainwater before feeding houseplants
- Feed strength in watering cans and self-watering reservoirs
- Pond or aquarium water, for a lovely home education project
Why we like the Spider Farmer meter
- Five readings. pH, EC, TDS, temperature and salinity in one pen.
- Accurate. ±0.05 pH, with ±2% on EC and TDS readings.
- IP67 sealed. Waterproof and dustproof, with a cap to protect the probe.
- Rechargeable. 600mAh battery charged by USB-C, rated for about 300 charges.
- Calibration included. Buffer powders at pH 4.00, 6.86 and 9.18 to keep it accurate.
pH meter questions
What pH should hydroponic water be?
Most herbs, salad and vegetables are happiest between pH 5.5 and 6.5. Check after adding feed, then adjust gently if needed.
What is the difference between EC and TDS?
Both show how much feed is dissolved in the water. EC measures conductivity; TDS converts it into parts per million. Use whichever your feed chart gives.
How often should I calibrate a pH meter?
Every few weeks with regular use, or whenever readings seem odd. Mix the included powders with distilled water.
How do I look after the probe?
Rinse it in clean water after each use, keep the cap on and don’t let it dry out.
The details
| Size | 181 × 44 × 38mm |
|---|---|
| pH | 0.01 to 14.00, resolution 0.01, accuracy ±0.05 |
| EC | 0 to 9,999µS/cm and 10 to 200mS/cm, accuracy ±2% |
| TDS | 0 to 9,990ppm and 10 to 200ppt, accuracy ±2% |
| Temperature | 0 to 60°C |
| Salinity | 0 to 25% |
| Rating | IP67 |
| Power | 600mAh rechargeable battery, USB-C, 5V 1A; no mains plug needed |
| Warranty | 1 year (Spider Farmer) |
What’s in the kit
| Component | Quantity and measurements |
|---|---|
| 5-in-1 meter | 1, 181 × 44 × 38mm |
| USB-C cable | 1, 60cm |
| pH 4.00 calibration powder | 1 sachet |
| pH 6.86 calibration powder | 1 sachet |
| pH 9.18 calibration powder | 1 sachet |
| User manual | 1 |
In the box
Everything listed above. A USB plug is not included; any phone charger works.
Clear water, happy roots, no guesswork. That’s the idea.