The water I use is processed through an Eco water filtration system which uses reverse osmosis and removes all chemicals and minerals that make our water hard. I try to keep my fish only, 40gal. and 150 gal.Tanks between 1.021 & 1.023. The reef tank is about 50 gals. and I try to keep it a little higher, 1.022 to 1.024. Reef has an led light with only 8 hours of white light and the other 2 get 12 hours of regular white tank lights. I have a gentleman from a local saltwater fish and tank company come out to the house every couple months to check them. I get confused about the other chemicals he checks for. I have clean up crews in all of my tanks. My two freshwater tanks are doing magnificent. This brown algea is making me nuts. What's even more frustrating is my reef tank has 2 small areas of this evil stuff developing but I think the crabs and snails are keeping it at bay. What other info. might you need to make a fair assessment?