I'm just finishing up my fishless cycle now.
When I planted the tank, I had a couple of hitchiking snails. wasn't sure they would make it through the high ammonia/nitrite levels initially, but they did.
Initially had a couple full-grown ramshorns, some other sort of tiny ramshorns (not just juveniles, the shell shape is different then juvenile ramshorns of the same type), and a few tiny pond snails.
About 2 weeks into the cycle, I had a microfauna boom - tons of copepods, lots of snails, some daphnia, free swimming nematodes, some planaria, a few insect larvae (mosquito, and possibly bloodworm?). more recently I've found hydra, and a leech.
Anyways, once I had more then a couple snails, they seemed to keep the driftwood clear of fungus, but I only had a couple smallish patches up until then.
So, If you want, I guess you could try snails