Is there a minimum amount for deposits and withdrawals?

Yes.

To keep transactions efficient and cost-effective, Pebbles has a minimum of $10 USD (or equivalent) for both:

You won’t be able to process amounts below this limit. If you try to send less than $10, you’ll see an error message prompting you to enter a higher amount.

This minimum helps us reduce network fees and maintain fast, low-cost service for everyone.