My girls have been on Fromm's Gold for probably the last 4 months and they have been doing great. However, I would like to switch them over to grain free. I was reading about the different foods and thought I would try them on Orijen...they liked it but with the higher protien level they both had diarrhea after just eating a few pieces for a snack. So, I bought a small bag of Wellness CORE but I'm not sure about that one either so I visited the Fromm's website (should have done that first

) and I see they have a grain free kibble.
So, my question is this...since my girls are used to Fromm's foods, should I stick with their grain free kibble? Fromm's is also a little lower in protien and I think I'm more comfortable with that. Would the same brand name make the switch easier for them or will it matter since one is grain free and one isn't?
I know Wellness is an excellent food but it's 34% protien and they are used to 24%...the Fromm's grain free formula is 30%.
Any opinions or guidance?