!help! Issues with Lyretail Kilifish

[Ailuros]

I have a heavily planted 20 long, containing a pair of aphyosemion australe, 3 sparkling gouramis, and a group of 6 pygmy corydoras. The female kili has had issues since being introduced to the tank, her stomach seemed larger than usual and she had swimming bladder issues. She has been in there for a few weeks now and is able to move between water coloums and eat fine, but is just slightly tilted. The male kili has recently (within the past hour or two of posting this) started showing issues. He can't seem to flip himself upright and is having issues swimming. He seems to be gasping for air and having a really hard time getting around. Upon seeing this I did tested water, everything was near zero besides ammonia, which was slightly higher than normal - nowhere near fatal. I did a 50% water change and dosed two tablespoons of salt. Is there anything I can do to help with the male kili or did I just end up with bad luck. If the male passes will the female be alright without a mate?

[Armiyana]

Honestly, fish are so sensitive at times, it's hard to say what will happen.
Personally I would have set up either a smaller quarantine tank for the pair when the female first started showing issues, but especially now with them both having issues.

Is the water particularly hard? I know the water where I am is TERRIBLE for killis
I've heard peat moss can sometimes help them out as a lot of killifish can become 'belly sliders' and have swim issues if it's too hard.

[Ailuros]

I introduced them as the first fish in the tank. After a few weeks of the female progressively getting better I assumed it would be safe to slowly add more fish. The female appeared fine in store and was showing no issues with swimming or any tilt. I believe it was transportation that messed with her swim bladder and caused the issues as she seemed fine in all other ways (curious, eating well, not gasping, no fin damage, etc). I started dosing salt after I noticed the issue and was doing 50 percent water changes often. Our tap water is slightly hard, but it seems odd to be causing issues this far in. Not to mention there is driftwood in there that should still help a little to reduce that hardness. But, I will definitely look into peat moss and get it in there asap. I'm not home now, but I'm pretty certain after how he was looking before we left that he's a gonner. The female had been inproving and gaining better colors since being introduced to the tank. They were both very active just the night before and were eating well (frozen bloodworms, frozen daphina, and bugbites). I'm unsure if I could've done anything to prevent it other than trying to lessen how hard the water is, which isn't too bad in the first place. Everyone else in the tank seems fine, no gasping or swimming issues.
If the male is indeed dead, would I need to rehome the female? Do they do okay without a mate? The pair I had had spawned in the past, and both seemed to be doing great (besides for the females swim bladder issues) up until today.

[Ailuros]

I'm sad to say that the little guy has passed. I just wish he could've gone in a better way, or just prevented it in general. I'm not even sure what the reason behind it was. Everyone else is still fine, water quality is good, little hard, but fine.
All I have to ask now is should I rehome the female? Will she still live a good quality life without another kili in the tank? Any other reason why he could've passed or is it just bad luck?

[Armiyana]

honestly, i don't know. I only know a little about killis and never actually tried keeping them.

sorry to hear about the little guy. I wish I could offer advice on the female. Maybe the shop would be able to take her back in? I know some of the fish stores near me will if it's an odd situation like this.

[Ailuros]

Thanks, I'm gonna look more into keeping just a single kili. I want to see if I can eliminate her swim bladder issues before bringing her back in (clean water, salt). Everyone else is still okay, it doesn't seem like his issues were contagious.

[Bogertophis]

Best of luck with her- sorry you lost the male. Wish I could help you but know zip about keeping fish.