Mr x can't see the red stuff in the link but my guy at lfs says sees it all the time and not to worry about it plus it comes off easy. Thing is that I was using crap phos test kit so thought it was good but got lfs to test with hanna and was over .20 so now got one myself to keep better control off it. The past few months have been hell, I upgraded to led and got loads off brown crap taking over but after a battle it's all gone so moving to next thing.
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