The Tidemark Federal Credit Union All Credit Levels is a cdfi lender from Tidemark Federal Credit Union. The annual fee is $10. The ongoing APR is 11.50%. Rewards: Members can earn up to $500 per calendar year by referring friends to Tidemark personal checking.. This product reports activity to your personal credit report. Tidemark Federal Credit Union is a community-focused financial institution located in Seaford, DE, offering a range of banking services including personal loans, mortgages, auto loans, and credit cards. They aim to serve individuals and families in their community, providing financial solutions that promote homeownership and community development. Services include: personal loans, mortgages, auto loans, credit cards. US Treasury certified CDFI Credit Union in Seaford, DE. Membership required.