Personally I wouldn't. It won't last. Toss it and get another bath.  I have an acrylic bath, paranoid about it cause it's also a spa bath. When painting the ceiling he wanted to get a ladder in it, with towels after I forbade it, but I forbade that too.

One crack and it's all over....

I painted that bit above the bath myself by balancing awkwardly on the edges in bare feet....