GFO changed color

I just changed my GFO. I use it in a TLF reactor. It had only been 2 months since my last change. This time (first time for this), the GFO had changed to the color of cement - and was wanting to lump together. Anyone had this before and can tell me what happened????? Over the last year my alk has been raised. Use to be I had a hard time keeping it above 8.5. Recently it was running 9.5 to 10.0 Could that have had any impact??

 

2 months! I've always used a smaller quantity and change about every 2 weeks.

 

If its not tumbling pretty good it will harden up like that