Hair algae

Make sure the nutrient levels in your tank are good (<10ppm nitrates and ~0 phosphates). If there is a lot of it growing, you're going to want to manually remove it by hand. Try to keep it from breaking down into pieces and floating around the tank by grabbing chunks. This is easier said than done, but just do your best. Continued aggressive manual removal, low nutrient levels and snails (turbo or cerith) will definitely keep the problem in check. Just be patient, it won't go away overnight. Cheers!
 
If you're running carbon you might try chemi-pure elite instead. It will remove a lot of things... and phosphates. And I'm going to double up saying to be careful while removing it by hand. If you succeed in getting a piece out that's a good thing. If you get a piece out but in the process spread little pieces of it everywhere it's a bad thing! lol.

Don't feel like you're losing the war. You'll soon find the cause of the growth, and then it won't get larger... then your removing will knock it out.
 
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