I have elevated levels of iron and manganese in my deep water well (50 meters) and I was recommended a AIO filter with katalox light. This filter takes care of the iron and egg smell but do not touch manganese levels. Seller says my PH needs to be 8.5 for it to take care of manganese and my PH is 7.8. They now want to sell another backwash filter with lime stone (?) media to rasie my PH. Is this the right way to go or should I look for something else? I'm pretty satisfied with my water as it is but I get a somewhat funny taste from it making coffe and tea and I think my stomach reacts somewhat on this manganese. Might be my imagination. Getting rid of some of the manganse would be a good thing of course.