Because I once had a kidney stone, as advised, I drink 2+ quarts of water a day. What struck a chord with me was that when I get into a rhythm during a hectic trading day, I don't drink a thing before 4 PM so I DON'T have to leave the computer :O)
This is incorrect. The part where you said "can only trade in margin accounts" is wrong. If you're labelled a PDT you must have over 25k to keep a margin account. If you do not raise your funds up to 25k most places will change your account over to cash only, some will actually lock it fully; although just making the account a cash only account will satisfy the rule.