Check selenium. After reading chelation materials, I've seen several folk say they found selenium to ease the crankies.
Folk chelating out mercury and the like do a lot of mineral replacement, so experience the patterns that effect mood.
Selenomethionine is the reccommended supplement, 200-600 mg in porportion to how much Iodine you do. Are you using it?
Potassium can be another element, but I'd look at Se, if you don't have any intake. Don't by yeast-based selenium supplements, they do damage and increase candida growth.
Selenium balances the Iodine in the thyroid, easing up the production of hydrochloric acid. It's possible that you end up cranky if your Se reserves and pulled to the thyroid to protect it in the midst of the HCl production. I think the HCl production is part of the body's defenses against infectious agents in the bloodstream on the way up to the brain?
Read yesterday that the thyroid helps cleanse the blood.
Iodine Forum folk here reccommend Lithium orotate to help further protect the thyroid from overload, it helps distribute the Iodine better throughout the body by lowering iodine thyroid levels.
I use Li aspartate myself, since Li Orotate (at 5mg) is a sleeeeep agent ;)
Low doses on some things, high doses on others, shave a pill, take two of another *whistle*