Nice freebie! It definitely looks like a monti. I’d say it’s probably an encrusting monti but it’s hard to say for sure. They’re pretty tough and adaptable corals. It should adjust to your light - I think you have the Red Sea LED, right? That should be enough light. Youll want to treat them like any other sps and eventually think about monitoring the “big three” and test for calcium, alkalinity and magnesium. My .02 would be to put it on a monti island. They’re fun and grow fast but be warned that you can always have too much of a good thing. They’ll cover whatever they’re on before you know it