My dogs LOVE to watch my snake eat too.

I think those weights should be fine, but I would invest in either the clips or a screen lid that locks. My snake used to get out all the time, but now I have a lid that locks and she hasn't gotten out for like 3 years or so now.

However, my dog has jumped on top of the tank so many times now that the screen is broken, so she could get out.

Luckily my living room is so freaking cold she won't dare leave her heat pad, so I doubt she would escape. As soon as I have enough money here I need to buy a new one.