Do you have any ideasWelcome, Careful with all this shims under your stand you are causing the stand to be point loaded into them
just a thought but maybe cut full tapered strips of something so there are no voids. if stand sags there is machine of tank failure putting strain on the seals. I just don’t want to see that happen. I would send pictures if stand framing as requested above. but it looks like a 1 x ? factory stand at first glance.Do you have any ideas