If I stretch it to much then the sides bow in which is a pain. Need a little thin brace bar or something to keep it stretched outwards?

What about gluing an acrylic rod into the center after stretching the mesh? Could even be on the underside to help hold it up?

Never seen a tulle fabric bleed. Ive used coloured and plain mesh and tulle and what not from my mothers fabric cabinet for years as media bags. Including whatever colour thread in her sewing machine at the time to sew them together. Never had bleeding other associated issues.

What about something inside of the rails to stiffen it up and prevent bowing? Would have to be light and ridged

Little off topic but what are you using as clips so that the lid sits on the inside of your tank.

I got corners that have a lip on them. You can also use the little aftermarket glass clips

Where did you buy these from. My corners are flush so I have to have the entire lid sitting on the rim of the glass. Yours looms much better.

I bought a bunch off a guy who worked at a glass shop
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