I think your "ivy" is a Pothos. Was it labeled as Ivy?
I am not so sure giving them some fertilizer is a good idea - too late now :-)
Sometimes just leaving a plant be for awhile is better than too much TLC.
Like I said, chances are your plants are just showing shock symptoms from bringing in. I have about 100 plants I brought in over the past several weeks and some look horrible.
Was the 50s you mentioned Day or night temps?
