HCA: Hermit Crab Association

Hello! We just made the DIY tupperware water dish for our crab so that he can submerse himself. He has buried himself (hoping he will molt!) and is not using it now... And I saw two little white organisms swimming around in it today. They look like worms and are only a few millimeters long. What do I do to get rid of them???

Also, We are in the process of finding a new glass top as we saran wrapped the mesh one we had but fruit flies found a hole and have expressed interest in moving in, a sentiment we do not like. Has anyone had this problem and been able to rid them of the tank? Tried just catching them but they dig in the sand and I can't find them.

Thanks!

Sounds like maggots. I would sterilize the water disc with vinegar, rinse it in spring water, and put it back in.

I don't think maggots would be in the water dish only. I would just wash out the water dish and refill it and see what happens.
As for fruit flies, you can put a 'home made' fruit fly trap (ie- with water and cider vinegar and soap) outside the tank to catch them.