At that temperture(25c), was your developing time less than 5 minutes? Kodak specifies that using times shorter than five minutes could cause uneven developing and blotching. I would think that 25c would have a time considerably shorter than five minutes. You may want to consider tempering your chems to a cooler temperture to bring times up for more even developing. I am a stickler for 20c and no more than 21c no matter what. Shaving time in processing does not result in proper negatives.