I just wanted to say firstly its good that you are taking chlorella and also I would look to spraying your anus (sorry to be crude) with Colloidal Silver .
It kills the bacteria that is probably lurking in that area causing the smell, its that old bacteria thing again but its so true...the colloid has alot of uses and you can put it anywhere without harm. Id give it a try. Spray it on after washing at night but dont rub it off by drying it let it sit there.