sliding top

I recently made a new lid for my smaller aquarium, out of clear panels of lexan (polycarbonate) that I got cut to fit at the hardware store. Even though it's not perfect (the cut was not right so I cut again at home with fine-tooth saw and tried to get it smooth with sandpaper but it has scratches on the edge now) I'm pretty happy with it. I followed examples found here. Basically it's two panes (most people use glass) that fit into this plastic piece meant to edge tile. One sits in the channel, the other rests on top, and to open you just slide one back. The op recommended having the bottom pane slide to open but after a few weeks of using this I found I prefer to slide the top pane, from the front. It sticks less.

My only issue with it is that contrary to what I read online, the lexan does start to sag in the middle. So I cut a piece of wire from a coat hanger for a center brace, and flip the panes each week to re-correct. Maybe the piece I got wasn't thick enough?

Here's how it opens. I was going to glue a handle on, then thought of drilling a hole just big enough to put a finger into (or drop food through) but in the end I just left it as-is. It's easy to slide open with a push of fingernail, and nudge close from the other side. I like this better than the hinged lid because I don't have to be holding the lid open with one hand while I'm doing something.

I wanted no hinge because it used to cut some light out- I have noticed the difference even visually not just plant response- and something other than glass because I don't want too much light coming into my low-tech system. This seems to be working. At least, so far.

It looks nice and sleek, too.