I concur with all the above plants, my golds could never get far. Nymphoides aquatica is banana plant. I had success with Rotala rotundifolla and R. indica. Aponogetons are good too. Egeria densa, and maybe other fast growing stem plants like Ludwigia or Hygrophilia. Just remember, anything that fits in the mouth goes in the mouth. Large leaved plants like crypts, aponogetons, etc should be great. Smaller stuff like Rotala they will munch on, but as long as you pick a plant that will grow faster than it's turned into salad, you'll be good.
"Everybody is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing it is stupid." - Einstein 5g rimless journal ~~~ 15g rimless (coming soon) ~~~ 20g rimless (coming soon)
Just wanted to share my current plants that I have had success with; Anubias, Amazon swords, Corkscrew val (this stuff is going crazy without ferts and sand as a substrate!), Java fern and some anarchis (spelling?). I will be adding many more plants in the future but so far, I have had major growth with these plants.
plants that worked for me were any floaters like water lettuce, salvinia, frogbit, pennywort. They reproduce faster than the goldies ate them in a LIDLESS tank. They also didn't eat the following submerged plants including swords, java fern, anubias. They did like to eat dwarf sag, ludwigia, and other stems.