Yes, you should use acrylic cement. A common acrylic cement brand is "weld-on".
You can go to any pet store and they should have this it's called All-Glass Aquarium Silicone it comes in black and clear and you can find it by the Algae scrapers works really good.
You can go to any pet store and they should have this it's called All-Glass Aquarium Silicone it comes in black and clear and you can find it by the Algae scrapers works really good.