I also prefer acrylic (I have both glass and acrylic). Acrylic is much clearer; it doesn't have that green tint that glass has because of it's material make-up. It's also WAY lighter and stronger, but a little more expensive, and way easier to scratch. You do have to be careful with them, make sure you don't hit the sides with rock, etc. Like mentioned above, use ONLY acrylic-approved materials to scrub algae off. Be careful with the floating magnets, if sand gets trapped in the scrubber you could scratch while cleaning the algae off. It just requires a little more diligence, that's all. If you do scratch it, you can buff it out, whereas with glass if you scratch - it's scratched forever. I'd go acrylic if you can.