guppies and salt

[masterfishes]

i herd that guppies prefer some salt in the water(same for mollies, platies, and swordtails) is this nessecary(ive never used it before).....usaully after ive had them for a year or so they just die...no disese or anything(they tend to start shimmying then spine bends and clamted fins and eat normaly up to there death) also i can never keep platies or mollies alive(havent tried swords yet as i dont have room right now)

 

[Tokis-Phoenix]

Long term salt use is bad for guppys, they simply aern't brackish and have never evolved in lakes or rivers that salt in them...Many guppys today are so inbred they only last a year or 2, which may be the case with yours.
Apart from mollys, where if you can they prefer salty water but it depends on wether they were raised in freshwater or brackish, salt should just be kept as a medical treatment with other livebearers.

 

[masterfishes]

ok well thanks for helping me figure this out