The surface of water has been changed to purple but the waterfog has not been adjusted to match. Even if vanilla waterfog colour is preferred it should be included in the mod for compatibility purposes. The screenshots below were taken with Biome Makeover installed alongside Bedrock Waters.

Mushroom Fields: the surface doesn't match.

Lukewarm Ocean: swimming in water!

I believe this is on bedrock water's end. They need to use the fabric biome modification api.

Feel free to open if that's not the case.