Hi. I've got 1 tbsp. aquarium salt per every 5 gallons water in my tank. I added it after the male of my pair of gold dust mollies died of disease relatively soon after I got them. Everything in the tank has been fine with it - platies, neons, and the cory too. I've heard a lot of people say not to use salt with anything but the livebearers, and definitely not corydoras, but it's had no ill effect on any of my fish, and I've had no problems with ich, other diseases, or excessive algae growth since I started adding it. Same thing with my work aquarium and that one has a cory, white clouds, and neons. It's been several months now and all the fish are active and healthy. There probably are fish adversely affected by the salt, but not any of the varieties I have. I'm not recommending it for everyone, based on the anti-salt opinions of a lot of people, but it's sure done wonders for my tanks, and those of my friends (who also have cory cats & the above mentioned fish, plus bloodfin tetras). I did a lot of searching on the net prior to adding the salt and the majority of the articles I found with respect to corydoras were that people that actually use it had no problems with the salt and their corys.