Went to a river and in Maryland and found these fish. Anyone know what kind of fish they are?

i woke up this morning to feed our guppies (3) & noticed this stuff kinda hanging out of him? off of him..?? i’m not sure. his back is bent which is also new & he’s slow at swimming, staying mainly at the top. has anyone seen this before?? it wasn’t there last night around 10pm when i turned off their light & said goodnight. i’m worried!

I just need a safe place to post where people understand. I am a new guppy parent, and all was well for the first week. They’re from pet smart (i know, not the most reputable). One had babies, but she succumbed to the pregnancy shortly after and went onward. Then, another seemed to be pine coning and developed dropsy and went onward too. This happened yesterday (the official mark of their first week with me). Initially there was only one fry, I woke up this morning to two more. I only have a male and female left out of the 3 females and 1 male I started with. It’s been a rollercoaster constantly testing water and checking them, but the last 2 plus the babies seem to be in great shape. I definitely need to get more plants, and do not plan to “breed” per se but allow nature to take its course however that looks each time. If the fry thrive and survive, of course I have the space and capacity to care for them but if they are eaten, I am okay too.

We currently have one guppy in our tank and 3 corydoras in a 45L tank. Other guppies we had unfortunately are not around anymore. We introduced 5 platies because they are less weak fish.

The guppy seems to be very aggresive to the platies. Chasing, nipping. We currently have the guppy isolated in a breeding box inside the tank.

Looking for general advice. Could adding more guppies help? I am afraid this will be many fish in the tank.

I ofcourse would like to not get rid of the guppy

I just started with guppies, got a 6 pack of assorted female guppies (one was a male endler lol) one of the females developed the cool neon green spots on both sides. I’ve been trying to find info but green spots on female guppies sends back a lot of different info. Just curious if anybody here what she may be. She was tiny when I got her so I never really noticed them until recently.

I have him in a tank with green neon tetras. His tail was fine for the first ~3 months and then within the last few weeks it has been stripping away. He’s the only hippy in the tank so doubt it’s fin nipping?