Just venturing a hypothesis, but I would say . . . Possibly. I weigh about 220 lbs, and I've stood in my 150g long without any issues. So, I would say that if you try to disperse your weight as much as possible, you should be safe, providing you aren't a large person. But, why risk it? I did a dumb thing several years ago when I stood in mine, and got lucky that it's still holding water. You can get long-handled scrubbers to help you reach. White vinegar works well at removing calcium deposits and other stains; just be sure to rinse well, as any residual vinegar will lower your PH. Cleaning water can be siphoned out. There shouldn't really be a need to get inside of it with the proper tools.