Need to get additional heater for your WC container.
Good for you to remind all that it need to be same temp as tank temp before using and testing SG.
Solution for me was to use hot water initially for mixing in salt mix...then waiting for it to cool to right temp...usually 4-5 hours.
I know exact amount of salt to use each time for my size container, so testing SG before using not a big issue (but probably should do anyway
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