Even hitch hiker snails survive in the tank during treatment. Even if this doesn't work, i know for ich it's fantastic.
I have a 55 gallon planted aquarium with fluval stratum as the substrate. Tank water is crystal clear. It is the only one that has ever worked as well as seeding the tank with a used aquarium sponge.
Niteout-ii. Amazing, lowers nitrites easily 25-40% over nite at minimum dose. By far the best nitrite removing and stabilizing product out there. The time it takes to have a zero ammonia and a positive nitrite (not nitrate) reading is as follows.