It depends on your budget and gambling habits. If you are used to wagering big, then you should leave a significant amount on your casino account. But if you are on a budget, you should count your winnings and deposits. For example, if you always deposit $100 and make $300 out of it by the end of the week, you can leave $100 on your account. The rest can be withdrawn.
https://casinobest.ca/faq/how-much-money-should-i-leave-for-future-depositing/