I assumed new users would have to create a new passphrase for their accounts, but not the original donors.
Using an online sha calculator is a potential risk because you are submitting your passphrase to someone else. I would recommend that everyone use a sha calculator on their local computer. You can use the command 'sha256sum' in your terminal.
It's probably best that everyone is going to use a new passphrase for their accounts. Now we just need the client to be hosted someplace besides Mega, so everyone can download it and create their accounts locally and not risk submitting their passphrase to an unknown server over the internet.
Think of the secret phrase as a private key/ brain wallet. It has nothing to do with the sha2 key made earlier and any secret phrase will open an account.