I got mine from Inland Aquatics. Inland is superb and I highly recommend them. Berghia are expensive and you need to get 3-4 at a minimum. You really want them to breed so that their offspring will be able to clean up anything the first generation missed. One note: turn off all flow except the return lines for 2+ hours upon adding the Berghia. They need little to no flow to get established.
In my experience, Berghia work very well. But they are not 100% guaranteed to eliminate aiptasia. In one tank, the Berghia ate all the aiptasia and I didn't have any new aip for months. All the Berghia in the DT died. It's impossible to get them out (IMO) and they only eat aiptasia. A few months ago I moved the rock around and voila, new aiptasia. So it might not be a permanent fix and you might need more Berghia at some point.
But they are very easy to breed, so if you have a good supply of aiptasia, you can make your money back (provided you find someone who will pay for your stock) and/or keep a steady supply. I would recommend a separate tank, like a 10 gal if you wanted to go that route. But you need a steady stream of aiptasia. I setup 2 10 gal tanks, 1 for aiptasia and 1 for Berghia. Then I have myself a constant supply of Berghia.
