I always found that baby bath a hassle so we only used it for about 2 weeks. I had a toweling sling type thing that was supported by a metal frame that let her lay on an angle in the bath (reflux means laying flat wasn't an option). It's an older version of the plastic bath seat I guess but they still make them. I just kept one hand on her. She didn't like getting her ears wet (still doesn't) so it was better keeping her head out of the water.

I've got a Bunnings kneeler too.