Any suggestions for how I can fix my bath. It has become quite porous and sucks up bleach, turning it yellow.
Welcome to the Bunnings Workshop community @jaxjef. It's brilliant to have you join us, and many thanks for your question about refinishing a bathtub.
It sounds like painting your bathtub would be an excellent solution. I'd recommend either White Knight 500ml White Tub And Basin Paint or the Rust-Oleum Tub And Tile Refinishing Kit. Both of these products will provide a durable finish and restore previously discoloured surfaces. I've used the White Knight product on my bathtub as the surface was heavily degraded. It's lasted several years, and I have been satisfied with the results.
Here's a helpful step-by-step guide: How to paint a bathtub.
Please let me know if you have any questions.
Mitchell