I do have to clean the glass in my main every 2-3 days, it's getting green, but my back wall glass never gets bushy! My PO4 reads 0, NO3 reads 0 (according to API test kits)! That red stuff were only in my refugium, growing only on chaetomorpha which i totally removed and left a small clean...
WOW, i knew it was something exotic, but never knew it was that invasive!
Just did some research and nothing came up! Do you have any info on that Cotton thing, like the cause and solution?