My first LPS

[FishFace28]

I bought both a hammer coral and an open brain at my lfs this weekend. I understand that the hammer has stinging sweeper tentacles and have given it a wide berth until I figure out how long they are. So, I guess that's my first question. Typically, how long are the sweeper tentacles?

As for the open brain (it's soooo cool), I have read that these are semi-aggressive as well. Sweeper tentacles for these, too? How much space do they need? I put my brain somewhat close to some mushrooms. Am I going to be sorry?

 

[Sheol]

Sweepers on brain corals? Well, all the favids have them. I've never seen a Trachyphyllia brain with any sweepers. So it all depends on what type of coral you really have. This is why its best to learn the Scientific names of your corals. "Open brain" is simply TOO generic. Ie:
Brain Corals
---------------
Platygyra
Trachyphyllia
Lobophyllia
Diploria
Favia
Favites
And so on. Perhaps a pic could help.
Anyway your Hammer (Euphllyia ancora) is famous as one of the most aggressive aquarium corals.

Sincerely,
Matthew
The above was not a criticism at all, just for more detailed info. Peace to all..

 

[FishFace28]

Looks like a trachyphillya. Sorry, I didn't realize there were so many kinds until I started googling the names you gave me.

I knew the hammer was aggressive when I bought it, but it's so pretty. At this point, it's got a clearance of approx 6 inches on all sides. I know this is probably overkill, but I want to wait and see instead of being careless with my other corals. I've been waking up in the middle of the night to see if I can see the sweepers (I'm a big dork), but I haven't seen anything yet.

 

[zeppelin]

Hammers do stretch out a bit, but at least not as much as frogspawn or torch (the worst euphyllia IMO). 6" is plenty of room. Just watch it and you will see what its reach is. Give it another inch or so to be sure, and for future growth, and you should be fine.