Im growing Amazon sword, Valls, Anudius and some floating plants with my geos and sevs at the minute.
One trick i found was to leave the plants in their pots, put plant food tabs in the bottom to develop the roots, and pack them in with fair sized round rocks.
One down fall is
A. (as japes said) Geos are bull dozers. Sand, gravel, small stones will all get moved.
B. They love to dig against anything solid (tank walls, stones, wood) so eventually, you just have a plant pot, tons of roots and stones laid on your glass bottom
My plants are growning well, no damage, lots of new shoots/plants now, but i do have to re-decorate the tank ever 2 weeks, and re-bury the roots.
Having a big root system will offer no safety from anything that digs.
Strong lights/fertiliser are your best bet. keep your plants strong, and your laughing, even if your busy re-decorating.