Slimes not spawning in "slime chunks"

I created a world then i update to 1.8.1 pre3. And i having the same prooblems, no slimes at swamp ( problably because is not the right moon ) and no slimes chuncks at all.

Probably i fixed this problem changing the chunk render from 8 to 12, then the slimes showed themselves.

This issue is affecting me in the latest release version 1.8.1. I see slimes only rarely in swamps, I think I have seen only two; possibly during full moon as reported by MCDodge, but I'm not sure. I have looked for slime chunks using third party software and slimes do not spawn in those chunks either (I checked at y = 26).

I will try changing the render distance as suggested by Guilherme and will report if successful.

EDIT: Have now been playing in the same world for over 3 months. I kill every slime I see and have amassed about a stack of slime balls. It is not that there are no slimes but that they spawn only very rarely. It does seem to have something to do with distance as a slime will spawn occasionally in the swamp next to my house but never when I am in the swamp.

Same problem, map started in 1.8

I am staff on a fairly popular server, and our entire server has been having this problem since we (recently) updated to 1.8. Some attention on this issue would be amazing. One of our admins has been running his auto-farm for 2 weeks and has gotten only a stack and a half of slimeballs in that time; whereas before it was very prolific.

By making a new custom world in 1.8.1 without caves, teleporting underground and clearing a 128x2x128 area I can almost instantly see that slimes do indeed spawn underground and in expected locations, as demonstrated in this screenshot

I was wondering if the non-functional slime farms in question rely on drowning the slimes because since version 1.8 slimes won't drown but will swim instead, what would explain why they don't work.

I can't speak for all farms in question, but I know my farm that has been having little to no spawn rate does not rely on drowning. Mobs drop money on our server, and slimes give great exp, so I have them drop intact into a chamber players can kill them in.

Just wanted to add my observations.

My Slime farm was built exactly like many other popular ones (7 levels, levels are 3.5 blocks high, light appropriately, etc.) , and I find a very, very slow spawn rate as well. Others have examples of receiving thousands of slimeballs within an hour or two. I might get half a stack in an hour, usually less than that.I just let the farm go for half an hour and got 6 slimeballs. I've verified I'm at a distance greater than 24 blocks, and within 128. I also tried around 40 blocks away. No change in the results. Before you suspect my "killing mechanism" of being faulty, I've also checked the room in 5 to 10 minute increments for an hour, and only saw one the entire time.

My seed is 2020255168143621720. It seems consistent across slime chunks I've investigated, however the specific one i'm in is 14 0 -4, or block x:227 y:15 z:-53 (give or take).

I'd be happy to provide any other information I can if needed.

No slimes spawning for me in verified slime chunks, steps to reproduce:

1. Create a world, pre 1.8 (ex 1.7.2).
2. Upgrade to 1.8+ (ex 1.8)
3. Find slime chunk, clear out area for slimes to spawn
4. Verify that slimes are not spawning or spawning exceptionally slow

Following the above method:

Version: Generated in version 1.7.2 and loaded in 1.8
Seed: 6355735297286536169
Chunks investigated: 8 1 8, 7 1 12
Results: No slimes spawning on either pad, travelled a distance of 25 blocks away from the edge of the chunk and witnessed. Cleared mobs by switching to peaceful and back to hard, same results.
Technicals: 768 spawning spaces each slime chunk yet no spawns, mob cap not reached
Pictures: https://imgur.com/a/c5RdV

> Results: No slimes spawning on either pad, travelled a distance of 25 blocks away from the edge of the chunk and witnessed. Cleared mobs by switching to peaceful and back to hard, same results.

You also didn't light up any caves or the surface, so low spawn rates are expected even if you switch to peaceful and back. And you didn't specify whether you tested in survival/creative or spectator mode (the latter won't work, IIRC).

>You also didn't light up any caves or the surface, so low spawn rates are expected even if you switch to peaceful and back. And you didn't specify whether you tested in survival/creative or spectator mode (the latter won't work, IIRC).

I also tried this with all surrounding caves lit up and the surface lit up, and I sat in creative mode for about 10-20 minutes but not a single slime spawned. Of course, that screenshot was a mockup created for the purpose of showcasing what happens, not really an accurate representation of how I tested what happens in depth (which I could post but would require a bit of work).

Edit: Notice the path to right in the photo
Edit2: Uploading pics of intensive testing method, imgur is down though

Here are photos/info from the intensive testing location:
seed: -1338829855858950965
chunk tested: -19 2 4
technicals: world created in 1.4, bug occurs in 1.8+
Imgur is down, so an imagebin link will have to do for now:
http://ibin.co/2848WgcAZKxf
As you can see, all the caves are lit up, including the surface

http://ibin.co/2849UdG4b6XV
The waiting spot to see if slimes spawn

http://ibin.co/2849xyrh0l37
The spawn pad

I have encountered this problem as well. I don't know the exact version but my world was created way before 1.8. Before 1.8, I had a lot of slimes spawning in this slime chunk. But now, I haven't witnesssed a single slime spawning. Haven't changed a single thing on the farm or even its surrounding chunks.

I have this issue also. At first I didn't realize that it was a problem with older worlds running on 1.8, but I've come to realize that this is the case with my world as well. Slimes spawn as normal at night in Swamp, but no slimes spawning below level 40 in areas that should be slime chunks.

same here, its really frustrating to have slime blocks out and no way to get slime balls especially because they barely spawn in swamps

I'll drop a comment here, since I accidentally posted a dup of this issue: this definitely affects 1.9 prerelease up to and including pre4.

Another observation: it seems that slimes spawn in the slime chunk if I go quite a bit away from the chunk.
Since they also instantly despawn when there are no players in 128 blocks range, it leaves only a very small window open for them to spawn.

I had 3 separate instances of them spawning in the farm and leaving drops, every time after I travelled away and returned.
Note that normally I don't go into 24 blocks range that'd prevent slimes from spawning.

Looking into an empty slime chunk, 1.9-pre3

Finding the slime chunk using AMIDST v4.1.

In the chunk contained at X:-217 Z: 70 as pictured in the other AMIDST screenshot and the the other screenshot as well. No slimes will spawn here even on hard.

Affects version 1.9.1-pre3

I created a world with the same seed (-1338829855858950965) in 1.9.1-pre3, went to the same chunk and cleared out a room, made sure to prevent spawning everywhere else within 128 blocks of the AFK point (by flooding it all with lava, in this case), and made sure to AFK at least 24 blocks away from the room. This guy spawned in under a minute.

The problem is for worlds generated before 1.8 and then upgraded. The first step is very important.

Generated the same seed in 1.7.2, went to the coordinates to make sure the terrain generated, then updated to 1.9.1-pre3, dug out the room, filled everything with lava, and got slimes again. Sorry.

I've been playing in the same world for over two years (see my previous post), I could count the number of slimes I have seen.. probably less than 20 in that time period. My base is between two swamp biomes, both are loaded when I am in my house. My base is also over 3 'slime chunks'. Not seeing any slimes. I now cheat in slime blocks when I want to do something with them.

Is this still an issue in the most recent versions (currently that is 1.12.2) of Minecraft? If so, please update the affected versions and help us keeping this ticket updated from time to time. If you are the owner/reporter of this ticket, you can modify the affected version(s) yourself.