Hi, welcome to the forum!
Sorry, really bad at plant id (this’ll be way off, just a random guess) but to me looks like some sort of hygrophylia. As to the red leaves (I know ever so slightly more about this)… it depends. Red leaves are usually better and more prominent in high tech (strong full spectrum lighting, co2, and fertilisers (especially ones that contain iron, I believe) than low tech setups. It could melt (I know nothing about cardinalis) but that is more likely if it was grown above water (emersed) or just finicky like a crypt. If it doesn’t melt, the green leaves are more likely to come though as new growth rather than all the red leaves becoming green or melting to become green.
Don’t take this advice like it’s from a professional (because it’s not
) and if you already knew all this, bear with me. Hopefully someone more educated can pick this up
.
PPJ