How is Bottom Timer Mode different from Gauge Mode?
A COSMIQ⁺ in Bottom Timer Mode is very similar to a COSMIQ in Gauge Mode. The difference is that the COSMIQ⁺ displays two additional readings: average depth and a secondary dive time, stage time.
The COSMIQ⁺ will start tracking these values when the bottom timer kicks in at the beginning of the dive and both measurements can be reset at any time during a dive by pressing the ADJUST button.