Does everyone add salt to all of their killie tanks?   I know with Nothobranchius you have to but what about to your soft water killifish? 

Hello Troy,

I only add salt to my soft water kilies if I have "velvet" odium problems, otherwise no.  When I do add it its only in the tank long enough for the fish to clear up then I remove the salt...

I hope this helps,

Jim Langan, AKA Webmaster

Thanks for the input Jim. 

Rick I.  is the expert on this subject... I hope he posts something for you!

I've added a tablespoon of non-iodized salt routinely to almost all my killie tanks for many years, as much out of habit as anything else.  It is worth noting that my tap water is from Lake Michigan, so it is only moderately hard and does not already have a high TDS to start with.  I can see how salt might be a greater benefit for those whose tap water is very low in mineral content, or a detriment if the tap water was is already mineral rich.

I have very good success with some killie species, and very poor luck with others, but I'm not sure salt plays much part in the difference.  I think my TDS and maybe pH are already too high for the truly soft/acid species.

I have recently withheld salt from batches of South American Annual species including longipinnis, nigripinnis, santanae, coamazonicus and constanciae, but did not see any difference in egg production, hatch or survival rates.

I always keep salt in with Nothos, and very rarely see any velvet infections, but since almost all my fish are exposed only to their siblings, I wouldn't expect velvet to have an easy pathway into their tanks anyway.

The best explanation I've seen for how salt could be beneficial is from the Aquariology books if I recall correctly.  Since freshwater fish expend energy removing excess water that enters their bodies by osmosis, perhaps reducing the osmotic pressure by adding salt to the environment allows that energy to be used elsewhere.