Ok your idea are good. Yes you can have a semi planted tank with shallow substrate. I’m am doing that now. I put my plants in planters. Makes them easy to remove if meds are needed. As to lighting something I’m using is the hyggar 957 led lights. Not to expensive and fully programable. Thing with your tank is the size. It’s an odd size. Will be very hard to find one light to cover so you will need 2. For 2 you’ll need a brace in the middle. I think your leant is around 78” so probably need 2 36” lights.
Your sump is only 40g? Is that 40g of water in a 75g tank? Or a 40g tank as the sump?
For your gravel/sand substrate black will show your discus darker and may pepper pigeon bloods. White will be brighter. Next sand is hard to clean where a fine gravel will be easier. When vacuuming less gravel than sand will be lost.
Here’s some pics of my flachen snakeskins and one of my tanks.
Attachment 132295Attachment 132296Hi
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