They should do fine at that temp. and eat/pollute the water a little less too. If your looking for max growth you'll need to kick it up into the 80s but they would likely outgrow your tank by Spring. If your looking to just hold them until Spring, the cooler temp and meager rations will make it easier. My pond is in the mid 60s and the tilapia are still active but they are slightly more cold tollerant species than yours.



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