From my experience, amanos will eat it before it grows but not when it is super long and grown. Once I manually removed it from my 10g my amanos took care of it and about 90% of it stopped coming back.
I had the same experience. Amanos seem to choke up when the growth is too massive. SAEs love this stuff and they are keeping it in check in my main tank. I have yet to fix my nitrate issue so I still have it in my main tank (@ Christmas moss) but I'm hoping for it go away once I've fixed my nutrient imbalance.