When it comes to fish, the looks of the food very seldomly plays part in weather they will eat it or not. - In tanks anyways..
What u should try 2 do is makin the pellets smell/taste like ur jars favorite food. Mine loves shrimp, so what i would do is to take a glas with very little water, squeeze the shrips juice in 2 the glas and then trow the shrips in. Then trow in some pellets.
This will make the pellets absorbe the shrimp juice/smell/taste and it might work on ur jar. It's worth a try

I've done this with allots of fish and it has worked 9/10 times
BTW, once u put some pellets in the glas, put it in the frigde for 2-3 hours before u try feeding ur jar with it