Here is a picture of my 10 gallon, UNS60 lagoon. I have 3 mangrove pods that are starting to root but have yet to show leaves. I'll be adding 2 more as soon as the weather gets nicer here (Boston, MA) and I'm not scared of the shipping. Let me try and give some insight to those asking how mangroves can die once introduced to a tank.The build for this tank can be found here.
Thanks for the great insight (your tank looks great!).
If you want a few extra pods, I have few extra (4, actually) in my reef (sg - 1.024) and I'm a few miles down the road from you (East Boston). Long story short, I wanted a pod or two to put in the rear chamber of my EVO purely for aesthetics (not to rely on for nutrient management). Another local reefer offered me a pod and when I showed up to pick it up, he had 6 wrapped up and packaged. Generous, but far more than I need. I may post them for free in another group, but DM me if you're interested. They're about 9-10 inches long with leaves and decent root length.