Now that I have my 3d printer up and running I can make some 3d printed screens. On my algae scrubber I found that algae became established quicker on the 3d printed screen compared to the traditional nylon mesh screen. It would be good to test this theory out more with other scrubber users and designs to see how well it stands. I created an initial screen just testing to see how well it looks. My printer still isn't calibrated properly but it does reasonable prints, certainly good enough for printing a screen. It's 2mm thick, at this thickness it's fairly flexible, and pretty strong. It's printed with ABS, but there are many other filaments available, such as nylon. You can get transparent nylon filaments, which may be a bit better. But I've found ABS works very well and is reef safe. The screen I've printed has holes in it like the nylon mesh, but it's hard to know how important these holes are. To me it seems they would increase agitation as the water hits them, which would probably increase algae growth, but it's just a theory. You could also create a flat screen with small raises and bumps which may do the same thing without the holes. Having the holes there could also allow more light to reach the algae, at least until the algae growth becomes dense enough to cover the holes, so it's hard to know at this stage what design would work better. My screen is just flat and it still worked very well. I only have the one reef tank which has a submerged scrubber on it, so I can't do much testing. But I can print out screens and ship them to people for testing. Let me know if you want one. I have a build volume of 20cm by 20cm, but as I haven't done a tonne of printing on it, I currently don't want to print a screen bigger than 15cm by 15cm. If you're keen, PM me or reply here. I will charge for this (based on the size you want printed), the price will generally be under $10 USD. That includes international shipping anywhere in the world.