Brown killer algea! HELP
So I have kinad been letting this problem go on for a while now and it has really gotten out of control. I hit a last straw when I got back from a 10 day trip and my Fox Tail was dead and the other plants have one foot in the grave and another on a banana peal. I don't know what to do about it and its been going on for about a couple of months. None of my fish have been affected and thats kinda why I let it get out of hand I guess. Any suggestions on how to get rid of this dark dirty brown hairy algea would be great!
4x42"T12, 8 hours a day
Just started excel this week, prior to that nothing, no CO2.
6 discus, 6 cardinals, 2 Bristile nose plecos
Bristlenose plecos and random small snails don't eat it ( and i think one of those two might be eating my swords!)
Tank: 72 gallon bow front, 85F
50lb organic potting soil, 50lb eco complete, 75lb black sand.
110 Aqua clear and 75 gallon sponge filter
thanks for all of your help!