I had an issue with the glass top having condensation and blocking light so I decided to make my own top using screen mesh (the aluminum one looks inline with the rimless look as opposed to the fibreglass ones). If I had the clear plastic mesh, I'd have used that. Bulk Reef Supply has them available. For the frame, I got some stainless steel rods from the hardware store. Can't remember the size exactly but 2ft of it was perfect for bending it around the rim. I think this would work great to accommodate other equipment like your heater for example. I made a hole for my co2 tube to go through as you can see in the top part of the pic just beside the filter. Likewise you could probably bend a lil notch into the frame to accommodate your chord. At the end of the day, it'll sit flush ( its supposed to unless you get the bending angles off a little).
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