It is not uncommon for the 1' and the 2" amplifier heads to leak water at a very slow rate or to "discharge" a mist of water when the heads are fired. The primary cause for this condition has been the degradation of the Nd: Glass rod thrust washers and/or rod O rings used to seal the end of the Nd: Glass rods to the amplifier head. To date, this condition has only existed on the 2" diameter heads, but this condition could also apply to the 1" amplifier heads
Identifying type and location of a leak
Signs that a water leak exists:
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Complete this procedure on each end of each amplifier head where there is suspicion of a leak, Or use several optics/mounts at different ends of amplifiers at one time to minimize the time required to identify leaks. This technique proved to be a simple and accurate way to determine the location of water leaks that only occur when the head(s) are fired.