I have a 40 L tank, (starter one) I have a soft water filter that I use salt, they have said the salt dose not go in to the water I use, the salt is to clean the two tanks within the unit, just wondering if anyone else has this and did it effect your fish? Also I want to have within my tank neon’s and guppies.
Do you mean a house hold mains feed water softener? Without knowing exactly the make/model and how it functions I cannot say for sure. I’ve been looking for some general information and the best I can find is this http://askville.amazon.com/problem-water-treated-softening-system-fresh-aquarium/AnswerViewer.do?requestId=3611932 It seems to be regarding “water softening pillows” mainly though I would assume your system works on something similar.
It may be worth while you having an HMA or ideally an RODI system setup and using that for your water changes then using remineralisation additives to balance the water chemistry back out.
As the article says most tropical (certainly Amazon based) fish prefer softer water however simply doing ion exchange doesn’t quite cut it so it entirely depends how your water softener is working.