skimpy
Fishaholic
Hi Amanda, I have only just got to read you post, and wanted to revisit the subject of salt. I would say that the salt was most probably the reason your fish died. Plec's do not like salt, it burns there skin. 
and yes there are some other fish also do not get along with salt either(I think someone mentioned loaches above).
Anyway, salt does not dissapear from you tank like some substances. i.e. medications are in the water for x days and then they are gone. If you have a charcoal filter it pulls out chemicals and anything left over from meds, but even that does not pull out the salt. Once salt is in you water it stays and if you were adding salt every time you did a water change, depending on how much you added it may have been getting stronger each time.
The "saltless" water changes you do in the future will slowly dilute the remaining salt in you tank, so eventually over a period of time your water will become saltless, but it will take a little while before it is all gone.
I suggest you keep an eye on the remaining plec to make sure he is OK and certainly do not add any more fish (that do not like salt) until you are sure that the salt is diluted enough.
It is ok to use salt to enhance medications or treat illness but find out about your fish and what their tolerance are first.
By the way I had one stupid lfs tell me to add salt because it makes there colour better. I said is that ok with all fish or just some, he said no problem, salt does not bother any fish.
Good luck
and yes there are some other fish also do not get along with salt either(I think someone mentioned loaches above).Anyway, salt does not dissapear from you tank like some substances. i.e. medications are in the water for x days and then they are gone. If you have a charcoal filter it pulls out chemicals and anything left over from meds, but even that does not pull out the salt. Once salt is in you water it stays and if you were adding salt every time you did a water change, depending on how much you added it may have been getting stronger each time.
The "saltless" water changes you do in the future will slowly dilute the remaining salt in you tank, so eventually over a period of time your water will become saltless, but it will take a little while before it is all gone.
I suggest you keep an eye on the remaining plec to make sure he is OK and certainly do not add any more fish (that do not like salt) until you are sure that the salt is diluted enough.
It is ok to use salt to enhance medications or treat illness but find out about your fish and what their tolerance are first.
By the way I had one stupid lfs tell me to add salt because it makes there colour better. I said is that ok with all fish or just some, he said no problem, salt does not bother any fish.
Good luck
