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Mini-secchi disk

Developer: Brewtek (with Plymouth Marine Laboratory)
Contact: Stefan Simis:
Supporting materials

Video: How to deploy a Mini-Secchi disk
Presentation guide: Deploying the mini-secchi disk

Further information

Secchi disk measurements have been used to record water transparency over hundreds of years, and are used as a proxy for eutrophication in international water quality monitoring programmes. Recently, a simple hand-held device was designed to measure the Secchi depth and water colour (Forel-Ule scale) of lake, estuarine and nearshore regions. The device is manufactured with marine resistant materials (mostly biodegradable) using a 3D printer and basic workshop tools. It is inexpensive to manufacture, lightweight, easy to use, and accessible to a wide range of users. It builds on a long tradition in optical limnology and oceanography, but is modified for ease of operation in smaller water bodies, and from small watercraft and platforms.
As part of ongoing development, MONOCLE has partnered with Brewtek, who designed the device, to provide further support for enhanced data flows and analysis. A new mobile App is designed to collect photos and the disk has been expanded with a clip to attach pH paper.
The 3D-printable design is particularly useful in community, educational and hobbyist settings.
For larger projects, mass-manufacturing is desired and this is currently being set up, with the first units expected to be available mid-2022.

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