Combine CRC32(), MD5() && SHA256 to make a Salt Combination is too much ?

Combine CRC32(), MD5() && SHA256 to make a Salt Combination is too much ?

The problem maybe that it would overcharge the server Memory while
Creating Hashes and maybe twice while loading it.
So did you think is better to make a function that specializes in this or
just use the default SHA256 instead?