wat is your tank size and your chemical readings. usually a little salt and frequent water changes about every day would help bring it down. and try to raise the tank tempareture. same procedures as you have read but i think that ich will mostly target your fish not plants and crustaceans. but if somehow they have "ich" it might not be "ich" may be something else. other wise do water changes, put alittle bit of aquarium salt if you got any and tank medication that specifically treats ich. please be more detailed. thank you and good luck. more people will see this thread and will help you if i am not sufficient