The most common cause of a goiter is lack of iodine, ...Even with the right amount of iodine, the thyroid gland can swell, creating a goiter. This can occur in any type of thyroid disease, including hyperthyroidism, hypothyroidism, thyroiditis, and thyroid cancer.
Shock treatment powder bags. Skim off whatever algae you can from the pool using a pool skimmer. Scrub the inside edges and walls of the pool with an algae brush to dislodge stuck algae. Purchase sufficient amounts of algaecide, as noted in the instructions on the bag, that match the total gallons of water in the pool.
A high pH level can prevent the chlorine shock from properly killing the algae. Be sure to test your pH before adjusting, with a fresh and reliable test strip or test kit. In order to clear a pool suffering from a severe algae bloom, a chlorine level of about 30ppm is preferable for optimal results.