I’ve been toying with material ideas to help with this very problem!
The stand that came with my R450 isn’t particularly well done, and I’m thinking of building a new one with a similar finish…
https://www.reef2reef.com/threads/the-frankenreefer-450.1147222/
— it’s a 5ft tank, with a 4ft sump; so I’m leaning towards double doors on the stand…
— everyone does wood doors, and it doesn’t always fit a stand’s finish unless you paint everything…
— so, why not use the likes of marble or porcelain wall tiles on a plywood/etc backing for doors? — the tiles are rarely over 3/8” thick, thus weight per-door would likely be <20lbs!