While looking around for a glass cover for my 40 gallon, I finally found one that was at a decent price. It read '36x18'. I instantly purchased it since it was the only one that I could find. When it arrived at my house, I noticed it came in a surprisingly small box. To my amazement, it was actually in two pieces. It was meant for a tank with a center brace.

This left me at a loss, because I still needed a cover for my tank to avoid evaporation and flying fish. Not wanting to get 'duped' again by buying one that was meant for a center brace, I promptly went to my local glass shop.

I was able to purchase a piece of plexiglass at 1/4 of an inch thick, cut to about 35x15 inches. I then measured out for both of my filters as well as a small hole on the size of the cover for my heater cord at 1" in diameter. I found a handle with a sticky pad on the bottom and was able to make a handle for the front of the cover. It's really light weight, so I can pick it up and back against the wall to do aquarium maintenance and feed my fish. againstallodds made a good point about drilling a small hole in the front of the cover to be used for feeding and picking up the cover. He also made a great diagram that can be used in making your own cover. The great thing about it is that it's very affordable and you can make a custom cover for ANY tank design. Even bowfront, pentagon, cube, or wavefront.

Diagram was reposted from againstallodds post in the Freshwater section.

I've been buying the Marineland version from PetsMart. They are all in one piece, except for the strip in the back which can be cut to fit around heaters and filters, etc. They also come with a plastic stick on lid handle. The largest size I purchased was for a 30 gallon and it was in one piece. I think it makes for a cleaner look than a regular hood.

I tried the plexiglass route and it just came out looking too rough. You need the thicker stuff... rather, I did, since I use light sticks that lay directly on the back half of the glass, instead of using a hood. However, even the 1/4 inch bowed in the middle. I cut it to fit two pieces, with the total depth so that an inch or two was open at the back for equipment. The front piece was narrower and served as the lid to open for feeding, etc.

Here's a pic of my 30 with a Marineland glass top. You can see the lid handle in the middle front of the glass top.

I tried buying a glass cover for mine, and I actually succeeded, until I found out it was made for a center braced tank, which mine wasn't. It's very difficult to find covers for odd sized tanks. 18" wide for example, especially on a breeder tank. It's a little rough with the plexiglass, but I'd try and go the next step thicker than 1/4". Mine's starting to bow just a little bit, but it still looks great and certainly does an awesome job.

How about getting picture framers to cut glass to size for you?

My dad does picture framing on the side, so I get him to cut hoods for me when I break 'em. ;)

I like the ones that hinge in front of the light, if anyone knows how to make that hinge from two pieces of glass, that would be good knowlege to have.