Transparency Tubes

Transparency Tubes Help Estimate Stream Quality as it Relates to Suspended Materials in Water

Just as a Secchi disk is used as a measure of lake quality, Transparency Tubes are a great reference for the study of water quality. The 1-3/4"-dia. clear PVC tube is marked in cm from 0–120 with a Secchi pattern at the bottom of the tube. To use, the Tube is filled with water and drained off using the drain tube until the Secchi pattern appears. The height of the water column is then recorded. Each reading becomes a reference for measuring changes.
No. 224196 is 120cm tall for use with the GLOBE program.
No. 111360 is 60cm tall and is widely used in volunteer stream monitoring.