THE ARTIFIOIAL PROPAGATION OF MARINE FISH
33
high summer air temperatures. As already mentioned, low-wattage
immersion heating panels prevented undue cooling of reservoir water
in frosty weather.
Herald et al. (1962) and Wood (1961) have studied the use of ultraviolet light for bacterial control in sea-water circulations; our 1961
system waa based on Wood’s design. The sterilizing boxee (Fig. 8)
FIQ. 7.
COMPRESSOR
System for sterilizing, filtering and cooling reservoir ma water
1961. (After Riley and Thacker, 1963.)
: I ,owestoft,
were constructed from 13-mm resin-bonded marine plywood lined
with epoxy resin, each box measuring 60 cm x 30 cm x 30 cm overall.
The lids contained two 16-W low pressure ultra-violet discharge tubes,
backed by an aluminium reflector, Water entered the box at low
level and passed over a longitudinal plywood weir before overfbwing
into the filters. The bactericidal efficiency of the system could not be
tested before installation ; an opportunity to do so occurred later on
at the Fisheries Laboratory, Burnham-on-Crouch, Essex.
For test purposes, 2026 1. of turbid estuary water in a concrete
33
high summer air temperatures. As already mentioned, low-wattage
immersion heating panels prevented undue cooling of reservoir water
in frosty weather.
Herald et al. (1962) and Wood (1961) have studied the use of ultraviolet light for bacterial control in sea-water circulations; our 1961
system waa based on Wood’s design. The sterilizing boxee (Fig. 8)
FIQ. 7.
COMPRESSOR
System for sterilizing, filtering and cooling reservoir ma water
1961. (After Riley and Thacker, 1963.)
: I ,owestoft,
were constructed from 13-mm resin-bonded marine plywood lined
with epoxy resin, each box measuring 60 cm x 30 cm x 30 cm overall.
The lids contained two 16-W low pressure ultra-violet discharge tubes,
backed by an aluminium reflector, Water entered the box at low
level and passed over a longitudinal plywood weir before overfbwing
into the filters. The bactericidal efficiency of the system could not be
tested before installation ; an opportunity to do so occurred later on
at the Fisheries Laboratory, Burnham-on-Crouch, Essex.
For test purposes, 2026 1. of turbid estuary water in a concrete