Razor is a good option for GLASS, but I had the algae dots on a acrylic tank.
If you've NEVER used a razor for algae removal you can cut INTO the glass/seal if you get a bit impatient.
The curious fish I was referring to were betta fish.
I have rosy barbs too, but none of them were inquisitive enough during maintenance to take a ride though the siphon tube.
ANYTHING that reduces the chance of scratching the tank is worth it to me.