UK seller 
80 x  PH Strips Full pH 1-14 Test Paper Litmus Testing Kit

Measurement Range 1 – 14 Ph

Ideal for monitoring water feeds and nutrients of young/old plants/trees in the nursery or orchard or greenhouse or hydroponics

80 strips in total
How to use?
Immerse a small tester paper for half second, then comparing paper colour with chart colour:
1-3 indicates "Very high acidic".
4-6 indicates "Acidic substance".
7 indicates "Neutral".
8-11 indicates "Alkaline".
12-14 indicates "Very high level of Alkalinity".
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