I want to put 2x 4' tanks beside each other and just looking for inspiration for bigger stands.
I use commercially available 1000 kg steel racks .
While each shelf can carry the 1000 kg even the 440 kilograms of two 4 foot 55 gallon tanks over time has put enough of a bow in each shelf for me to recommend adding a leg in the middle on day one.
Not an ideal recommendation for these Chinese brand racks.
In my case the 2400 mm / 8 foot racks required me to remove and re position the end braces to fit two 1210 mm / 4 foot tanks. I am still very happy with the outcome but it requires a bit of planning.
No need to limit yourself to two side by sides when you can have two pairs of 4 foot tanks stacked on top of each other easily with a steel rack.
You did ask for inspiration?