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.
When you add mangroves, you really should know where they are coming from so you're able to properly acclimate them to the salinity. By properly acclimate, I mean over the course of several weeks. I was lucky enough to purchase these three rooting pods from a supplier that grew them in water with the identical specific gravity I keep my tank at. Drip acclimating a tree will do nothing, you need to slowly increase or decrease the salinity of the water you're keeping them in until it matches that of the tank they'll be going in. You may think your mangroves are fine without doing this but the damage from being in hyper or hypotonic solutions may not show for up to two months in my personal experience.
Another fact people fail to realize is that mangroves are able to grow in saline conditions because they exude salt through their leaves (most species anyways). If you're going to maintain healthy mangroves be sure to spray down the leaves with RO water every once in a while!
For those asking about how to get roots like you see in mangrove groves there is a simple trick although it will take YEARS to work. Use some sort of float, I've used Styrofoam squares in past tanks, to support the pod so it is growing at the top of your tank in suspension and the roots will eventually grow down and, with time in patience, support the plant.
I hope this little bit of information helps anyone trying to keep mangroves! Stay tuned for my mangrove display coming with my new SPS tank upgrade later this year

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