Guppys or White Cloud Mountain Minnows as Feeders for Axolotls?

IMO, guppies can be kept in coldwater conditions, maybe not as cold as 16 C, but maybe 19-27 would be a good range. Axototls like warm water too, so I would just buy a heater.
 
No, axolotls will get infected and die in warm water.
 
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