Lane you have just begun to feed these things and it takes lots of time especially when your giving it mixed with the old food she is used to getting an recognizes
so of course this is going to be something that will take time...a couple weeks is simply in your case not enough time for this bird to adjust.
Dont switch just keep giving her what you have as in her case where she doesnt get much in the line of excercise the BROWN IS BEST..as its less fattening...but realize just like a kid or adult even ...they will gravitate to what they have been given and are use to for so long over anything new to be tried.
as far a what your asking regarding moulting food...i simply, myself, do not condone ANY commerical seed.
When fed with whole organic grains and seed mixes as most of us now do ...the rest of what you buy for this or that or treats is no longer necessary as they get what they need from a more nutritous diet...so you actually SAVE money...as you dont need to buy supplements, vitamins, or treats.
persistence in getting a bird to eat fresh veggies and new foods is a must...and mixing with old foods they are use to is a uphill battle for sure but not impossible...as a result you WILL SEE waste. Thats logic.
i must also restate...those are not HULLS in those pictures you posted those are the WHOLE seed...
the HULL is simply the casing of a seed or grain, with the fruit or meat inside of the seed or grain removed by cracking it open when the bird eats ...and looks different.
Two very different terminologies when referring to SEED, or HULLS, and whats is trying to be conveyed for better understanding.
remember also if or when you should try to buy your own organic seed that canary seed is also sometimes better known as ALPISTE SEED...so check under both.
also just closing in tupperware Lane is not good for storage as no matter what they say it doesnt BURP out all the air an so seed will age fast and lose its fresh delicious taste quicker...like fresh bread from day old bread the difference is huge.
So you would be better sealing in heavy duty freezer type zip lock bags and rolling it to push out all the air you can before zipping close. If done right you will see the seeds visiably stick to the plastic as if static electricity is making them do that.
it doesnt take long at all for their food to age and lose freshness at all...and if it doesnt taste good because of this well there ya go with another uphill battle trying to get her to eat anything new.
bird food...people food...dog or cat food...ANY food is best if somehow all is done to keep it as fresh as possible for as long as possible...tupperware is not the way to go or any of those types of plastic containers.