My current scrubber had been working well. Its a 4"x8" screen with dual 100watt CFL bulbs. I dont have any pictures, but recently as of about a week or so, I have cyano red and green growing out of control in the sump area where my scrubber is. The walls are covered in red cyano covered bubbles and the floor has a garden of 4" cyano slime strands. I also have a bright neon colored green, hard to remove slime algae on my screen that is around the edges that I assume is also cyano. The center of the screen is a yellow green normal looking algae. So far this is only in the sump where there is low flow and 18 hours of light. The DT looks great and has super clear water. Levels all read good. Here are some pics from start up to when it had a nice layer growing. Here is what I believe is the issue with my current design. My slot pipe is only 4" long and is getting flow from a direct connect MJ1200 so flow should be plenty. 1. The spillage of light and low flow in my sump has caused the huge red/green cyano outbreak. 2. The CFL bulbs and reflectors are large and bulky, get salt splash, and spotlight. That said, I want to try and limit light spillage and upgrade to LED's. My screen size of 4" wide by 8" tall and the flow from the MaxiJet 1200 seems to be right on, so I dont think I am going to change that. Looking around I ordered this DIY LED kit with 8 660nm LED's and a 600ma driver. 8x3 W LED With Constant Current Driver Kit. DIY item The only thing I m having a hard time deciding on is how to mount the LED's and contain the light. I like the idea of building a black box with clear sides that has black pockets on the clear sides to hold the lights and sit this on some top braces. But I have some questions. 1. how far should the standard 3 watt LED's be from the scrubber screen? 2. I was going to mount the LED's to Aluminum U channel I have laying around. How hot do the LED's get? Can they directly touch the clear acrylic? 3. I am trying to keep things as low noise as possible. Is there a benefit/drawback from having an open bottom box so the screen touches the water vs having a closed bottom box with adjustable drain and emergency over flow?