I posted this on gardenweb too and someone suggested some sort of migratory fly eggs (maggots). I'm thinking mosquito larvae also.

My numbers
FC 3.5
CC 0
pH - new pool and SWC so pH rises quickly. I try to maintain 7.2-7.5
TA - 100
CA - 330 - this has risen from 200 over a few months
cya - ~45
water temp 85
salt 3200