Would this be what is being ask about?
https://www.daf.qld.gov.au/__data/assets/pdf_file/0004/64039/Fact-sheet-for-Tanking-recommendations.pdfThe Queensland Government has developed
best practice guidelines for the handling and
storage of mud crabs from harvest to table.
These guidelines were developed as a way to
reduce the stress levels of muddies, decrease
mortality after harvest and to increase the eating
quality of the catch.
This fact sheet provides key information on
holding live mud crabs in aquariums or tanks.
Tanking crabs
Recover crabs as per Recovery Procedures
Factsheet. This will minimise contamination
in your tank’s water.
Use clean seawater and monitor water
quality regularly by checking:
temperature (18°C – 25°C)
pH (7.9 - 8.1) use sodium bicarbonate to
increase
salinity (15 - 35ppm)
ammonia (<0.1mg/L)
nitrate (<50mg/L)
nitrite (<0.3mg/L)
Conduct regular water exchanges as nitrites
do not break down readily and will reach
toxic levels over time.
Provide adequate but not vigorous
circulation and/or aeration.
Install a bio-filter to suit the tanks
volume/stocking density.
Cover tank to reduce exposure to light,
breeze, evaporation and disturbance.
Ensure crabs are tied tightly.
Check all crabs regularly – one dead crab
can cause others to die.
Do not feed crabs as it is unnecessary and
may effect water quality.
Larger storage tanks – as above and:
Store crabs in lug baskets lined with shade
cloth to stop leg tip damage. Raise baskets
25mm off the tank floor
Pack crabs tightly to reduce movement.
Alternate holding systems
Several innovative systems have proved useful.
Consider a spray tank system. This will:
minimise stress to the crabs
provide a constant (ambient) temperature
produce less maintenance on system
provide a fail safe in power outages
promote self cleaning of crab waste
encourages a low weight loss %
Install a solid false bottom floor with
drainage to a submerged pump.
A garden irrigation system or similar will
create even mist.
Use saline water for short-term holding.
Ensure the surface area is large enough to
hold crabs stacked a maximum of three high
– this enables easy checking for mortalities,
reduces crowding and allows adequate
exposure to mist.
Crabs should be covered to reduce
exposure to light, breeze, evaporation and
disturbance.
Drain and clean tanks regularly (crab
through-put dependent).