I'm sorry to hear of your experience.
I have no children, but I don't like second hand smoke (regardless of its source) and I similarly was extremely upset during a stay at the Turtle Bay Resort on Oahu, formerly a Hilton property. I too love keeping my balcony door open and listening to the waves - that's why I'm there - but some schmu@k kept smoking a cigar on his balcony so like you, I also had to keep my door closed.
But I don't see how you can fault the Clearwater Beach Hotel. You said security tried to find the source, and it doesn't sound like you tried to get moved to another room when you first encountered the problem, so what more can you reasonably expect from the hotel management?
I appreciate your sincerity! I also book oceanfront rooms to listen to the ocean not to have my doors shut. I want to make sure everyone knows that I do not blame the hotel for this issue and I want to thank the hotel security for attempting to find out which room this was coming from. In the end they did not find the person smoking the pot and I did not request a move to another room either. I did find out today that they have only four suites that are similar to mine in the entire hotel and they were all taken. They then said that if I would have asked for a different room they would have downgraded us which I would not have liked. In the end the hotel did everything in their power to remove the issue from the property. I am just sorry something like this even occured.