I ordered 1000 meal worms which will arrive today. Just realized I haven't bought them grit yet (planned to pick it up tomorrow) but they have been outside on the sparse lawn several times and spent a few hours scratching/pecking etc... Can I feed them some meal worms today? Or should I wait until AFTER I buy them grit? Would they have picked up enough sand and such on their own outdoors? The soil here is sandy would they probably have enough to process a few meal worms?