shredded fins

Somebody please help me I’ve had 2 guppies die and have shredded tails (my other 4 have badly shredded tails too) I treated fin rot and did a water change etc it’s still happening I think the guppies may be hurting each other as in my tank I have 4 guppies 2 adf frogs 2 ghost shrimp and two...

I recently moved and now live in a place that runs off of city water. I purchased the API water conditioner (store was out of Seachem prime -- I hear that is the best you can get). I also transported all of my cycled media to jump start my cycle. I haven't been able to test the water parameters...