custom plexy lid top help

Stainless steel is stainless because it's got a high chromium content. Now chrmium is toxic, it's true, but it's not water soluble. The chromium near the surface oxidizes, forming a protective layer around the metal. The fish cannot be harmed by this unless they eat the entire piece of hardware.
 
I had to make a plexi one temporary until I could get glass cut and replace the glass one I broke, I used Duck Tape to make the hinge and the handle to open it with hehe.
 
They do make plastic hinges. Do a google...the availability may be limited but they are out there.
 
plexiglass

I have a plexiglass lid for one of my 20 Long's and if the plastic isn't thick enough it will bend and collapse. I would make sure it is 1/4" at least or you'll be disappointed because it WILL bend! And also if you are putting your hob on the side of the aquarium you wont need to make hinges just glue you a piece of 1/2" pvc pipe about 1" long to the top of the plastic for a handle and you can remove the whole lid when doing maintenances
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I have found that 1/8" Lexan is a lot more rigid than your standard cheapo hobby 1/8" plexi. Its a bit more expensive but won't sag in the middle as quickly or easily as the cheap stuff.
 
I would personally get a stainless steel piano hinge the length of the top and epoxy it at your seams on the top side this would also add rigidity to your plexi to eliminate the sag. HD or Lowes has every thing you need to get this done.
James
 
hinges

You can purchase the brown or black hinges that come on the class canopies online for around 2 dollars per foot.
 
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