Seneye Products > seneye slide NH3/pH > Strange pH > NH3 readings > Is my seneye+ slide damaged

    Every effort is made to ensure that when seneye+ slides leave our factory they are manufactured correctly; however, on odd ocassions slides can become damaged during handling or fitting.

    We recommend that you read the links above to help trouble shoot. Please feel free to contact us for further help and guidance.

    If you have a pH issue such as it is not reading correctly then please read here.

    Sometimes it is possible to tell whether a slide has been damaged by examining its sensor pads. A slide has two sensor pads, one against a white background to read pH, and one against a transparent background to read NH3. On a healthy slide, we would expect the colour to be consistent across a sensor pad, and for the colours to be between yellow and olive green:


    small Healthy slide .026NH3 8.12pH.png

    Chlorine Damage

    If your slide is submerged in tap water, or if tap water added to your pond has not diluted enough by the time it reaches your slide, the chemistry on the sensor pads may be damaged by chemicals that are sometimes present in tap water, such as oxidisers like chlorine and ozone. If oxidisers are damaging your slide, your readings for NH3 may fall throughout a slide's lifetime and then jump back up again when a new slide is fitted. Upon examination of the slide, the colour on the NH3 sensor pad may look patchy or faded:

    small bleached by chlorine.png

    On this slide the sensor pad for NH3 has started to change colour, so there must be some NH3 present, but the colour is not continuous across the entire pad.

    Stained Slides

    Some chemicals may stain the sensor pads rather than harm the chemistry, and since a Seneye sensor calculates pH and NH3 values based on the colour of the sensor pads, this can affect the accuracy of readings. The sensor pads on a slide stained by chemicals may be a colour other than yellow or olive green, and the colour may be discontinuous with a sharp divide. We believe that the slide below had been stained by chlorine:

    small stained by iodine.png

    Chemical Damage

    Some very strong chemicals may react with the sensor pads in ways other than bleaching or staining, but slides damaged in this way may still be detectable upon examination of the sensor pads:

    small destroyed.png

    It is clear this slide has been damaged because the pH sensor pad is a colour other than yellow or olive green, and the colour has bled into the surrounding white backing.

    small something bad.png

    The colour on the NH3 sensor pad for this slide is not consistent, and the texture looks very spongy, different to the flat sensor pads of a new slide.