It can be difficult to tell just by a picture. It does look bloated for one.
More information please.
What are your tank water's parameters?
What are the tank mates?
Size of tank?
Was it's poop white and stringy?
Was it's belly that bloated before death?
Did it have issues swimming properly before death?
I had posted earlier today about fish loss after treating for internal parasites but the consensus was that it was my water parameters that caused the deaths. High nitrates to be specific. But I did a 40 % water change and used prime this morning prior to leaving and then come home to this one dead and another one just away from dying. I took video but not sure how to upload that. All the guppies are lethargic. I have lost 3 in 24 hours now along with 1 neon tetra and 1 false julii cory.
This yellow ones tail looks ragged at very end and he is curling up toward top of tank.
I hate to say this but sometimes there is just no answer for this.
Last week I lost a Mystery Snail, no reason, just was gone one morning.
I'm no expert, but I believe that once they have been weakened by ammonia/nitrite/nitrate poisoning, sometimes it's too much, & their bodies can still give out even after being in clean water... however, hopefully the rest may still make it. I would continue to try and keep your water pristine - test frequently - and do however many water changes it takes (just don't shock them if your nitrates were up at extreme levels... keep dosing Prime every 24 hrs).
What were the parameters after you came home to find this one dead? Unfortunately, sometimes just one water change isn't enough, & it takes multiple w/c's to get params to a safe level. (Many of us have been through this) What are your parameters as of now? After you check, it wouldn't hurt to do another w/c with Prime.
NightShade I did another water change but I have both pre and post water change results. I will attach pics of results. Nitrates were 40ppm before change.
Post water change...I think around 20ppm.
I checked ammonia and nitrites and both are 0. I am waiting on my test tube nitrate test to be delivered. I know that is better. But this is all I have for now.
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