Those white bobbles that separate the swim areas have little creatures crawling on the underside of them! Pick one up and look under, not harmful but could be the cause you are commenting on. Just don't hang on them for swim support, dive under or pick up by the rope to pass by. One more little bugger to be aware of. This is too early for me to be commenting, some rules of language I believe I'm infracting on by ending my sentences with the words ON, And OF ... Later!