They can handle high flow if they are left to settle into the rock after introduction. I usually turn off all flow, at night and introduce. As soon as the scurry off to a crevice i turn back on flow.
They do take 2 -3 months to eradicate an infestation. They will quickly start to reproduce and after a couple of life cycles, the aptasia start to disappear. Once you start to see a noticeable decline in aptasia, it rapidly picks up speed.
Best part is they will eliminate ALL aptasia if you have propogation of the Berghia. I use a minium of 3 per 50gal to start with. More will speed things up, but they are rather expensive.
Typically I use them every couple of years because aptasia is introduced so easily. I currently have grow out tanks for aptasia and Berghia mostly because i think they are cool looking and i enjoy the challenge. If you are trying to raise, they are labor intensive for WC 's and growing enough aptasia (food source) to sustain a colony. Once established, they go thru aptasia fast!
