Can you take a picture of the feet so we can see if they are adjustable or not? Yes, they are not wrong that once you put water and everythin in the tank it will no doubt slowly conform. The problem is in stressing the tank while you do that(if I was going to try this, I would probably fill the tank up about a 1/3 or 1/4 full and let it sit for a while) I don’t know how much give is in the stand, it could flatten out rather quickly with very little effort or weight applied. I am not there to judge the rigidity of the Stand build so I cannot give you a direct answer on that. Just by twisting or moving the stand around you would be able to tell how much weight it’s gonna take or pressure to get the twist to come out of it. I would either flip the stand upside down on a good level surface and put like a board across the bottom with something of heavy weight whether you have exercise weights or something heavy to get the stand to readjust. Or you could put something flat like a piece of plyboard or something on top and put a bunch of weight on the top and then adjust that corner up and it will take the warp out of it. If your floor is perfectly level, and the feet are all adjusted at the same height if you slowly started to fill the tank, it might instantly come out of it. You’re gonna have to be the judge of that, if it’s compressed particleboard, there isn’t gonna be a lot of rigidity to it and it will succumb to the weight rather quickly and be a non issue