As said on Garfs Badass thread I am trying to create a larger area of 3D algae growth. The first attempt (which can be seen here ) wasn't very successful. There was a little 3D growth but not anything like as much as required (left it for 9 or 10 days) So this is the version 2 (video quality not good, but you can see what it is) I nicked Garfs cable ties idea and relocated the powerheads to one end of the screen. The overflow from the DT now discharges around the powerheads so that they suck in some of the air mix and blow it out across the screen as microbubbles. 2 x 15w CFLs replaced with 2 x 15w LED grow bulbs. No idea if this will work but here's hoping.