BGKs should be fed frozen or live foods, preferably bloodworms.
does the BGK have caves to hide in? they are nocturnal animals and are very light sensitive. without a dark cave the BGK may become frantic and stressed.
if you are using one of those "ghost tubes" that may not be a good enough hiding spot
"Atrocities are not less atrocities when they occur in laboratories and are called medical research."
George Bernard Shaw