Is the temp constant 25 degrees. I use an attic n it can get very warm at times. Try give em a right good watering but I wouldnt put any ferts in, y dont have t do that everytime. Water em till the excess comes out the bottom of the pots could be the soil nearer the bottom is too dry n although y dont want t over water em it does make em perk up after a good soak if they have got dried up. Im no expert but its what I would do. Durring the summer I came home a few time t find my plants looking fried n crappy gave em a good soak n put a fan on em for a while n they soon perked up. Im not sure if the ferts you are using are wrong or not I use bio bizz which was reccomended by the place I get my seeds from.

Hope this is of help