Nice looking tank Bob! Is that a 55g? All fancy goldfish or are there some commons or comets in there as well?
I kept some java fern and anubia in my goldfish 55g for a year or so. They sifted through it quite a bit, but for the most part it stayed intact. These were smaller sized goldies though. Not sure they'd hold up with fist sized fancies or a 10" comet.