Pufferpunk;3512022; said:
A 55g partially filled, isn't enough space for 3 archers.
I tend to agree, though a filled 55 is probably adequate.
If you went with the paludarium, I think you would resent the wasted space quickly. Few terrestrial plants do well with salt spray, so the lush planted look would be tough to establish above the water (I think), and there owuld be no action there anyway.
You will enjoy the archers more with a well decorated full tank, and you can train them to spit within the space in your hood. If no hood, then any suface clamped, propped, or otherwise placed above the water surface can have bit of shrimp or other goodies smooshed to the side for target practice.
I have tried growing mangroves on several occasions (red mangroves and white). I've had varied degrees of failure, and I've given up on the idea. I think adequate light has been my problem. Others have had success, though, so read up and keep us posted if you give it a try. I don't think they really add much to the "archer experience" that cant't be recreated other ways.
Good luck!
BTW, my experience is that most who ask for advice/opinions here are really looking for affirmation of their own preconceived ideas, and they resent contrary posts. WHile you should certainly take everything you read here with a grain of salt, your apparent willingness to consider (and even follow) other's recommendations is admirable and will greatly improve your odds of happy successful fishkeeping!!