What he said... 
There is one consideration which was mentioned to me by a local aquarist. Water conditioners that have gunk like aloe vera in them (here's my Stress Coat bash ) can actually harm fish when added directly to the tank, but in a rather counter-intuitive manner. I used the term "gunk" on purpose, they're thick and gouey, you add it to your water as you're filling and a fish swimming underneath is hit by a gob that gets caught up in its gills and stresses out or potentially kills the fish. Meanwhile you're testing your water and trying to find out what killed the fish only to leave it as an unsolved mystery.
I'm not sure how likely or possible the above situation is. I did lose an Oto with no changes to water params. while I was using Stress Coat, but I'm not going to come out and blame the conditioner, it's merely a possibility.
I have, incidentally switched water conditioners to the cheaper Insto-Chlor, but that had nothing to do with the possible harm to fish of Stress Coat. Simply that a) our local water is Cl2 only, no chloramines, and b) I don't like the idea of adding something unnecessary (aloe vera) to my tank. Whether or not aloe has healing properties for fish I don't know (it's great on sunburns though), but why add something intended to heal an injury that isn't there? Not to mention the price.
There is one consideration which was mentioned to me by a local aquarist. Water conditioners that have gunk like aloe vera in them (here's my Stress Coat bash
) can actually harm fish when added directly to the tank, but in a rather counter-intuitive manner. I used the term "gunk" on purpose, they're thick and gouey, you add it to your water as you're filling and a fish swimming underneath is hit by a gob that gets caught up in its gills and stresses out or potentially kills the fish. Meanwhile you're testing your water and trying to find out what killed the fish only to leave it as an unsolved mystery.I'm not sure how likely or possible the above situation is. I did lose an Oto with no changes to water params. while I was using Stress Coat, but I'm not going to come out and blame the conditioner, it's merely a possibility.
I have, incidentally switched water conditioners to the cheaper Insto-Chlor, but that had nothing to do with the possible harm to fish of Stress Coat. Simply that a) our local water is Cl2 only, no chloramines, and b) I don't like the idea of adding something unnecessary (aloe vera) to my tank. Whether or not aloe has healing properties for fish I don't know (it's great on sunburns though), but why add something intended to heal an injury that isn't there? Not to mention the price.
