cory and otto cant stand the dose of med.They will die.so like lonewolfblue,go for salt and heat method
Then how do you explain my cories and ottos surviving ich meds in the past?
You have to find the right kind of meds. If you want to use medications, don't get one that has malachite green or methylene blue. I think you can use them, but at half strength (so only use half the dose). I like to be safe, so I don't use those two. And you have to check ingredients, because even if they have another name, they could still contain one of the two.
I have found 2 meds that work well for ich and scaleless fish. Kordons Ich Attack and Kent's Marine RX-P. The Ich Attack is all natural and safe for scaleless fish. The Marine RX-P is also safe. It says marine and the instructions say nothing about freshwater, but it can be used in FW. I have personally used both and had no casualties. The RX-P is better IMO and works faster at getting rid of the ich. The person that recommended it to me used it with small Discus fry...with no problems. Raising the temp is also the thing to do. I have raised it to 84F with panda cories. I went up to 86F and lost a couple pandas once, so now I don't go over 84. Just watch the fish when you slowly raise the temp and make sure they are acting normal.
I also agree that meds will lose potency or expire after some time, so I don't think I'd stock up on them unless you have ich often.
Checking out the fish you are going to buy and the other tanks at the LFS well will help prevent ich. I know its sometimes hard to see it, especially when the spots haven't shown up yet, but inspect the other tanks too. I have been doing this for over 6 months, with no ich outbreaks.