Phenol Red Tablets for pH Testing

Overview

Phenol red tablets measure pH across the band that matters in treated water, moving through yellow to red as the pH climbs. Because pH governs how well chlorine disinfects, how aggressive a water is towards pipework and whether scale will form, it is normally read alongside the chlorine residual rather than on its own.

Key features

• Reads pH in the working band for potable water, pools and process water
• One tablet per test, so there is no measuring or decanting of liquid reagents
• Foil-sealed strips keep unused tablets dry until they are needed
• Supplied in the standard 250-tablet pack, item code TbSPpH250

Phenol red tablets specifications

Applications

Potable water and SANS 241 monitoring, swimming pools and spas, cooling towers and boiler feed, effluent treatment, and dosing systems where acid or alkali is trimmed to hold a set pH.

Why buy phenol red tablets from Hadron Group

Hadron Group supplies water treatment chemicals, dosing equipment and analytical products throughout South Africa and the SADC region. We hold phenol red tablets as standard stock in the 250-tablet pack, we can supply the matching photometer, cuvettes and spares, and our technical team will help you settle on the right test set for your plant. Browse the full reagent range or ask us for a quote.

Frequently asked questions

How does pH affect chlorine dosing?
Chlorine disinfects far better at lower pH. As pH rises, more of the residual sits in the weaker hypochlorite form, so the same reading does noticeably less work.

Photometer grade or rapid grade — which do I need?
Photometer grade is formulated for instruments that read a cuvette. If you work with a visual comparator or colour disc, ask us for the rapid-dissolving grade instead.

How should the tablets be stored?
Keep them sealed, cool and dry, and work through the oldest strip first. Once a strip is opened the tablets take up moisture, so use them promptly.