As reviewed above, dissolved oxygen is critical to the health of your pond.  Here’s a valuable instrument to help forecast DO trends and head off potential dangerous depletions.

The YSI Model 55 is a handheld DO measuring system.  It has a rugged, micro-processor digital meter with attached DO probe.  Cable lengths are 12, 25, or 50 feet.  The probe body is stainless steel to add durability and sinking weight.  A large, liquid crystal display is easily read in all light conditions.

The micro-processor performs self diagnostic procedures when the unit is turned on.  This step provides valuable information about instrument circuitry and ensures quality readings.  Temperatures are posted in Celsius and Fahrenheit.  Expect 350 hours use from six AA alkaline batteries.

The Y55D series features a detachable cable.  They’re accurate, durable, and have long been considered the industry standard.  They’re backed with a two-year warranty (one-year warranty on probes).