Now I hate to be the one to ask this.
Betta lover1507: Please don't take it as I am saying just get it over with. Sparta is a very stunted fry and from the sounds of it...doesn't seem like he's going t make it regardless.
Since he is still that tiny, it would only be right to cull him now before he suffers any longer. Wouldn't you think it is better to do than to sit around waiting for him to grow and eat and make you even more sad everyday with many other family and outside problems going on as well.
Yes. I have to admit Sparta seems like a trooper, but really he sounds like he won't make it soon. With the cold water and then warm water, not eating correctly, swimming problems, ect.
He has gone through a bunch and I am surprised as such a tiny fry he lived through all of this.
You are doing your best, but to my understanding, you honestly have no way of getting him to live and have the energy to be the spunky betta he sure is at heart.
If I was in your shoes I would see that culling him would be best to get him out of this constant suffering state. Then in the future when you are able to care for a spawn...heck...go for it.
You know that we can always help out with a bunch of things. I'm sure you can get the hang of it in the future.
Again this is not meant to offend you or to bring you down. I actually am aiming for this to be a learning experience.
I hope you consider it. I've heard many ways of culling fry and usually they are easy with small fish like this.
Best regards from me.