Thanks for your help..
 

yes, was feeding the nem a small piece of raw shrimp once a week. Would anyone recommend a different meal, or should I step up and feed it twice a week or even more?

Sort of a rule of thumb, the less light they receive, the more they need to be fed. Some people have never directly feed their nems, but still have large beautiful specimens. Keep in mind when you feed your tank the nem will inevitably get some food also.
Since BTAs come from such a wide variety of locations, its difficult to know for sure what any one BTA will recognize as food. So feeding a shrimp to one BTA may have good results, feeding it to another from a different location may result in it spitting it out later when you don't notice. All along you think your feeding it, but in reality, its somewhere in you tank being eaten by your clean up crew. A better idea would to get a few different ingredients, shrimp, mysis, silversides oyster eggs ect. ( no squid for BTAs as far as I know they always spit this out) Blend them together, and put the mush into a freezer bag and flatten it. Freeze it and when you want to feed, just break off a piece, thaw and feed it.