Did Stress kill my guppy?

[Noahspurlin]

Good morning folks, unfortunately my male passed away this morning. I have had him and a female since 2/2. I noticed at the beginning of quarantine that the female was food dominant and would pick on the male. Once I realized that she was nipping at his fins I removed him into a breeding container and supplied an air stone in there for oxygen. Today would be his third or fourth day in the breeding tub. I don’t believe he has eaten anything throughout quarantine. I have taken notes of all my water tests, besides ammonia. It was at 0ppm yesterday. I have also put down below the salt dosage. The last picture is from this morning 😢. If there’s any guppy expert that would know it would be much appreciated. THANKS 🙏 

Edited February 8 by Noahspurlin

[Guppysnail]

I’m sorry about your guppies. With no ammonia readings and 0 nitrate readings I’m going to say ammonia is what did in your guppies. Stress from the ammonia would have also caused fin nipping. 
How long was this tank set up?  If new did you use media from a seasoned tank?  

To add being weakened by potential ammonia adding meds could have added stress. Meds are very hard on fish. 

[Noahspurlin]

I tested the water the day before the fish passed and the waters ammonia ppm was at 0ppm in that tank. I used a sponge filter that has been seasoned for one to two months in my flower horns 75 gallon. I realized two days ago that when I was treating the tank I was treating it as a 10 gallon but it was a 5 gallon. They looked very similar in size the way I had them setup. The female was nipping at the male and chasing after him. I just believe by accidentally dosing ich x for double its recommended dose caused stress to the male and getting picked on by the female caused the death. Thank you for taking the time out of your day to respond it is much appreciated ♥️