I have a 70g hexagon tank attached to my system (see sig below) that has been developing over 2 years. I originally was going to do a seahorse tank, but decided it wasn't a good fit, so I'm doing anemones instead. I started with a purple tip cody, and in order have added: a huge green rhodactis, a green condy, 2 stone flowers (and one put out several 'pups'), 3 corkscrews and a good sized LTA, added about 6 weeks ago. I have a RBTA, a green BTA and some maxi minis in other tanks that will be added in soon. So far there has been no obvious warfare between the anemones. They are all just out of reach of each other and they have all stayed in place, more of less. I've had a stone flower move and 2 corkscrews have moved. But they have been smaller anemones and once they found homes they have been stable and appear to be doing fine. There is a mated pair of clowns (female is a cinnamon and the male is a tomato) along with a small blenny. I just added an orange file fish to help fight the aiptasia growth (I let it get out of control, my bad). The blenny has been in the tank for well over a year and so far both he and the file fish have avoided all the anemones. The clowns use the purple tipped condy as a host. The purple tip condy, the stone flowers and the corkscrew anemones were all collected in the Keys over the last 3 years (a couple of these were in my old 75g DT before I set up the current system).
The nem tank has less flow than the 180g DT and it is circular flow around the outer edge of the tank (being a hexagon). There is 1 MJ powerhead with a cheap rotating head for some random flow. The back half of the tank is rubble LR piled into a hill up against the back glass and the front half is 2" of fine sand. I have some red macro algae in there as well, and it grows better here than the chaeto in the refugium. I do not run carbon. I use filter socks on 2 of the 5 drains and not the drain from the nem tank. I have quite a bit of LR in the system and a 2' x 2' refugium with a DSB. The DT is loaded with a variety of corals, mostly lps and sps. The nem tank has a 250w MH and t5 actinics.
I hope some of that info is helpful. Good luck.