Bunny poop black and soft-ish(?)

[decountdooku]

Hello,

When I checked this morning, my bunny sat under my bed in the corner (which he rarely, if ever does), surrounded by weird, black, tarry poop. Some pieces of it are extremely hard, and other feel pretty soft.
He seems to be quite a bit less active from his usual jumpy, fast self. I'm quite worried.
The poops that are quite soft can be "rubbed" out on a tissue, giving off this green-ish color.

There were no changes in his diet, and while he still likes to eat, I feel like it's less than first, although this might be just a feeling.
Blue is about 1,5 months old, so I'm very worried about him.
Here's a few pictures to help clarify.

If anyone could point me in the right direction of what this might be, I'd be ever so grateful. I'm willing to go to the vet, but it's closed today, and it might be unneccesary.
If you have any more questions, or in need of some more pictures, I'd be happy to help.

Thanks in advance,
Daniel

 

[LavenderLopLover]

1 and a half months old is quite young normally rabbits are rehomed around 2 months old it is it could have been cecotrophes you would wanna watch him because of the fact that soft poops can turn into diarrhea ive never experienced before but normally with my young rabbits ill feed them some small amount of old fashioned rolled oats it helps with soft poops also whats his diet like does he have access to fresh hay at all times? does he get fed veggies? how much pellets are you feeding and what kind?

 

[Hermelin]

Myself when I see the pop changing form, I’ll put my bunnies on a hay diet until they are okay again. Then I will slowly introduce their food again, so I can slowly make sure what made their stomach get troubled.

I see in the pic candy with seeds, they are really sweet and so young bun shouldn’t have those.

Myself also have fed my buns those candies but it was only short amounts during a prolonged period depending on the size and weight of my rabbits. Told my dad to not buy them again, because those treats are really unhealthy for bunnies. Better to give small amounts of fruits, leafy greens and herbs.

If your bun it’s younger than 2 months you should only feed pellets and hay, nothing else. If he’s used with a few veggies from before it’s okay to feed them in a small amount. But nothing else.

You need to wait until your bunny get older to introduce new treats and veggies.

For example a small bunny should only get one small slice banana as a treat.

Larger bunnies can eat more while smaller bunnies should get less.

But your bunny it’s still a kit, so no treats for him until he get older. You can feed pellets as treat, don’t let it become spoiled like my indoor bun or else you will have a picky eater [emoji4]

 

[A & B]

No new foods at all (100% hay diet) until the rabbit is at least 3 months old. This is most likely the cause, as his digestive system isn't able to handle these foods.