Aquarium Tops

[Billinet at aol_com]

For years I've used 1/4 inch plate glass with one corner cut out for accessories.  I place the lighting fixture directly on top of that.  If the cover will be for than a foot or so I have it cut in half.  Greater lengths tend to crack from the heat of the light.

The cost is $10 to $15 for one to cover a 29 gallon tank.

The downside is that the thickness of the glass reduces the amount of useable light, by how much I don't know.  And, to my surprise, I've sound that the glass wears out over time and becomes almost translucent, due, I think, to interaction with hard water.  This takes a number of years, though.