Nice plakats... The left one is a chocolate, right?

Hmm.... I think as long as temperature not below the minimum req, and the fish are not directly facing the air conditioner, should be ok... They live quite ok I guess....

Do you keep you PC on most times? Then maybe keeping them near your PC could help to keep the water a little warmer... Radiating heat ma...

Oh, and do change them to a larger container if possible.... Heat lost harder..