Instrument: Zooplankton Pump - gas centrifugal

Instrument Short Name: Zoo Pump Gas Centrifugal
(http://vocab.nerc.ac.uk/collection/L22/current/NETT0146/)
Instrument Description:

The Pacer gas-powered centrifugal pump is a water pumping system for zooplankton sampling.

PI supplied instrument name: Zooplankton Pump - gas centrifugal
Dataset-specific description

Earlier three deployments: The end of a sampling hose was attached near the bottom of the CTD rosette frame. The hose was lowered independently over the side using the CTD to control depth and record conditions throughout sampling. A system was used that delivered approximately 255 l min-1 to the deck and cleared in less than 1 minute. Lines were allowed to clear between samples. On deck the water passed through a manifold and a reduced volume, 31 l min-1, was passed through a succession of small sampling nets with 40 µm mesh. Variations in flow, which are generally small, were monitored with a flow meter on one of the main lines from the manifold and were used to adjust flow rate calculations. Sampling in the small nets was timed with a stop watch, with a target of 1 minute (31 l) per sampled depth. Samples (up to 12 per cast) were preserved in a small volume of buffered formalin for later analysis.