Manny try to hold yourself from getting an anenome, I know they are beautiful and if you have a clown fish they are even better, but they are deaddly to SPS's and just about any other coral you have in the tank, most species like to move arround no matter how happy you think they are in the spot you put them they will move and when they do they will kill everything they touch in their way, I have lost several SPS's and a beautiful colonu of mushrooms (About 100 in one large rock) to an anenome that decided to go for a walk. That was the end of my love affair with anenomes
If you just have to have one, check with All Sealife on Pembroke Rd, south side in the warehouses just west of I-95. They usually have a couple, at reasonable prices (around 40-60 bucks.) Only problem is, you need to get one much larger than your clownfish, or it may irritate the anemone into moving into your overflow or filter. I've lost 3 that way now.
As long as the anemone is happy, it will stay put! Ive had a BTA for over a year now and it has been on the same rock since I got it. I keep it around the mid point in the tank and has only moved twince since Ive had it...and Ive had to move the Rocks around several times! If you have Clowns...you should have one IMO! Thats everyones favorite thing in my tank(not to mention I get free coral food from the baby clowns born every few weeks!)
I couldn't agree more with Roger... Not to mention that even the BTA's (a hardier species) are very delicate creatures. if you can't be disuaded, then go ahead, but clowns don't need anemones to be happy. In fact, clowns usually will find a substitute host. (In my case, the entire right side of my tank. She rubs and snuggles EVERY coral there.)
One last thing thesaent... I believe you recently moved to your 180. Even if you DID have an anemone, you shouldn't get it until your tank has had time to mature. I'd say at least 6months, preferrably a year.