MyCatsDrool said:
I have heard that it is better to allow the salt to dissolve in the tank as it releases more slowly that way, allowing the fish to adjust. But this is information from a book, not from real life experience. I have done this in the past. Should I change my technique?
I think it all depends on the current in your tank. I would imagine for this method to work well you want a pretty high current that will evenly mix the salt as it dissolves in a small spot. Otherwise you have a salt "waterfall" (you can see it for sure), or an area in the tank that has a higher level of salt than another.
If this was my tank, I'd first dissolve the salt in some tank water, then over the course of 1/2 hour or so I would slowly add in the salt water (ie every 5-10minutes dump a little more in near the area of highest current (say outlet spout of a HOB, or the opposite side of where the fish is (if they like to sit right under the filter).
Frankly, salt is about the LEAST harmful thing you can add to your tank in terms of stressing/hurting the fish, and as long as you don't make a concentrated salt solution and try to pour it directly on them, they will be fine.
I'd still do the slow addition however, but that's just me.
Story that somewhat relates to this post:
My friend who has had a 125g tank for several years had slowly had is fish die of old age. he was left with a huge 12" oscar (probably bigger), and a giant 20" common pleco. Once another one of his longterm fish kicked the bucket he decided he wanted a change in his tank, and wanted to go with CA cichlids.
He found a home for his large oscar, but decided that the pleco should stay. Instead of doing a slow addition of salt to get the tank up to where his new fish require, he boiled a salt water solution on his stove (I assume to get it to dissolve in such a high concentration), and then dumped the whole amount in his 125g tank. Now I imagine this is quite a bit of salt in that boiling water....
As he is starting to pour the solution in, he doesn't see his pleco coming over to inspect the area. He pours the full salt solution in the tank and moves to look in the tank. What does he see? His giant pleco is now sitting directly under the salt waterfall that is sinking like a rock to the substrate. Now fortunately I'll assume that the salt solution is no longer at a high temperature since it is falling through tank water, but needless to say the pleco was in for a rude awakening.
My friend says before he could scare the pleco away, the bolus of salt water drops all around the pleco. The pleco STOPS breathing (no gill movement), sits there for a couple seconds, and then the breathing rapidly starts again.
I would say that was quite a shock for the little (big) guy, but fortunately his is now king of the tank with the other cichlids.