Feel free, actually. I'm interested too. You can get good fixtures that have the mount built in. I don't know the brand but all it does is sit atop your trim and the outside of the tank.
The ZooMed fixture requires you to attach the mounts to the inside of the tank too. Allows you to shift the size to your specific tank which can be handy, but also prevents you from using a canopy. Yes, you probably could notch out glass to use the fixture, but you're going to have to take the glass off every time you want to get into the tank if you do that, and by that point it's more headache than it's worth.
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