Tylototriton kweichowensis 
i got 5 of these not long ago and its harder than a thought it would be to cool down the tank i have the tank at 65-75 depending on the time of the day i need them around 55-65 and i dont have a basement/garage to put the tank in...does anyone have any tips how i could cool down the tank?

i got 5 of these not long ago and its harder than a thought it would be to cool down the tank i have the tank at 65-75 depending on the time of the day i need them around 55-65 and i dont have a basement/garage to put the tank in...does anyone have any tips how i could cool down the tank?