Acan echinata aggressiveness/neighbors

[Fishbird]

For those of you with Acan echinata, how big is your tank? How many corals do you have and how long have you had A. echinata for? I keep reading that these are extremely aggressive and some sources recommend leaving a foot of space between them and their neighbors. Do they really need that much room? Would I be able to fit a couple of A. echinata, three Euphyllia and a couple other corals in a 40 breeder? Say each colony eventually grew to be 6” across.

 

[PedroYoung]

I've had several over the years. My current on is about 4.5" after 4 years of growth. It will occasionally act up, but the farthest he's ever reached has been about 2.5". here is a pic from when a snail pushed a frogspawn frag too close.
echinata blast-2 by Peter Young, on Flickr

Doesn't seem to mind when zoa's get close, but other LPS get him riled up.

This is a pic I pulled of the internet (not mine) several years ago to remind me of what could happen
AcanEchinata by Peter Young, on Flickr

INHO they're worth the risk, just be careful. Mine is on it's own rock so I can move it if other corals start to get close.
echinata-8 by Peter Young, on Flickr

 

[grisha]

They are monsters for sure. Lost corals to it, it loves soft acans btw. And micros

 

[Hemmdog]

Place them like you would place a chalice. They can sting things fairly far away, but they are no where near as monstrous as a lobo.

 

[grisha]

What I don’t like about them is echinata will actively reach out to neighbor at night to sting and kill. Chalice may let tentacles out along the flow and sting something on the way, but in now way as aggressive.