But now my problem: we are on height 16 and we have made a few tunnels and in each chunk a bigger place, I think this place is about 5x5x5 blocks tall. Big slimes require a 3×2½×3 space to spawn, small slimes require a 3×2×3 space, and tiny slimes require a 1×2×1 space (or 1×1×1 if the upper block is not opaque). I already had a slime chunk slime farm, and used the mushrooms to redo the lighting instead of making a swamp farm. If you're ≈20 blocks ftom that chunk, they'll spawn. 1. They are therefore very sensitive to. Regular mobs won't spawn on glass, or stained glass, so slimes will not either. The first of these are to build walls or fences around areas you wish to keep slime-free. My guess, mobs are spawning in other caves etc further away and on ground level. They can also spawn in swamp biomes between layers 50 and 70 in light levels of 7 or less. The only way to find. [more information needed] Big slimes require a 3×2. 278. It would not work at all in that case, unless you accidentally got lucky and hit a slime chunk, in which case the whole point of building in a swamp is moot. You can make a slime chunk detector with a green slime ball (which you can make from cactus through botania alchemy) and some pink elf metal. Another tip: create multiple levels in the slime chunk, and you'll get tons more slimes!I used the chunkbase site to find a group of 4 slime chunks not far from my base in 1. 1 - Slimes will spawn in a slime chunk in an ocean biome. Through the center of the chamber, make 10x10 platforms while making sure to leave a few air blocks to separate them. The first step to making a slime farm is to find a slime chunk. 5. One layer isn’t gonna net you a huge amount of slime, but if you don’t need that many, then perhaps 3-4 layers above and below y=10 would yield you enough. The light level requirement for slime spawning in swamps is different from that of most hostile mobs, which spawn only at light level 0. Find a dark spot. I have tried to stay away from the chunk for a while, but still no slimes will spawn. Through my experience slime spawns in slime chunks need alot of work to make them viable. You will need to be in an area between 24 and 128 blocks away for the farm to operate, and for best results you'll need to eliminate all. I'm not sure the issue. Slimes are bouncy, cube-shaped hostile mobs that spawn deep underground in particular chunks, or in swamp biomes. . v. ”. 8. Slimes not spawning in slime chunks on realms. com website, but since slime chunks in every version don't change as long as the seed of the world is the same, so I'm not having any problem with finding slime chunks. The technical answer is to dig out a complete slime chunk not higher than Y 39. 4 version (Spigot) I have setup for slime farm, but Slimes are not spawning. Make sure there are no caves with zombies or any other mobs in the vicinity. But I'd go on chunkbase, find a slime chunk instead and dig it out. It would not work at all in that case, unless you accidentally got lucky and hit a slime chunk, in which case the whole point of building in a swamp is moot. I'm digging out an area which should be a slime chunk to build a slime farm but so far no slime have spawned. ago. It's not possible to see these with a specified texture pack. His farm is in a Slime chunk though which should always spawn slimes. My slime chunk coordinates are 536,309 (x,z) and my seed is 8857034577360149641 if that helps with anything. This is your vertical position in the world. Slime spawning in swamps can occur between Y=51 and Y=69. Share. Slimes have a low chance of spawning compared to zombies or skeletons. 19 and Minecraft 1. • 19 min. Slimes won't spawn in slime chunk. Y=40 is the highest place they can spawn. I have been waiting for about an hour afk with the game active at. the-nord-jord • 9 mo. On average about 1 in every 10 chunks is a slime chunk, so a 4x4 chunk area should give you enough chunks to include at least one. Slimes don't care about light at all in slime chunks, so you don't have to worry about having too much light; just make sure no block is light level 0. Here are some reasons why they won’t spawn: Max Mob Limit in the Surrounding Area. 4% chance that you were just unlucky and there are no slime chunks. Only this time, no matter what I did, slime would never spawn. It is a slime chunk, and slimes are spawning in the bottom. A second option is to locate a swamp and make a surface trap, then light up the caves within 128 blocks of the trap and light the surface within 128 blocks (but leave the trap spawning areas dark). The slime. 1x3 space uninterrupted which intersects with the tunnel sides no matter which block is chosen in 3 wide tunnels since the big slime would spawn partially. Y=40 is the highest place they can spawn. 16. Or making a perimeter also 124 x 124 radius which also is alot of work. No mobs spawn, slimes don't even spawn at all on slime chunks. Slime make a distinctive squelching noise when they bounce, so you’ll know when one is near. If you do this in a corner and AFK at the top for awhile, you can just look down and see any slimes through your. According to the Minecraft Wiki: Slimes spawn only 1/10th as often as other hostile mobs, so they can be hard to find. Just to clarify some of the concerns and questions: Outside of swamps, biomes have absolutely no bearing on whether or not slimes can spawn. . As for slime chunks, I'm running a two chunk ilmango based farm and you can literally see the slimes raining down once you light up the perimeter. The space they spawn in must also be clear of solid obstructions and liquids. While chunk spawning always has a 10% success rate (not taking slime chunk chances or anything else into account), the success rate of swamp. However, just as with other mobs, slimes require an opaque block to spawn on top of. DiamondIngot, slimes are pretty common in swamps, so you can go hunting them right at daybreak (listen for the splopping sounds) if you just need a few slimeballs, clear out a few layers in a slime chunk and build a slime spawning area if you want a lot, or clear the slime chunk to level 43, put in multiple levels of spawning floors, a water. This means 100% of slime spawns will be blocked by a new moon. Find a slime chunk. In Minecraft, there is a certain limit to how many mobs can spawn in an area. Seems the slimes have a hard time spawning in my multiple worlds as well. Apart from spawning in swamps (added in 1. I found a slime chunk right inside my straight mine so I dug out a 16x16x3 chunk at level 19 and coordinates 71 19 -120. Chunkbase. Hi guys, I have an issue with my slime farm. 1 Answer. Slimes spawn in the Overworld in specific chunks below layer 40 regardless of light levels. Slimes aren't spawning in slime chunks, unless the spawning mechanics changed. I started on y=11 and waited around by the chunk for anything to spawn, but nothing has, but I. But an XRay would help to see all the way to bedrock to see caves in which they may spawn in. Ive heard somewherw that slimes dont spawn below y=37, so maybe you can try that. 5, using Fabric client-side only), however, slimes will not spawn. Do /kill @e[type=minecraft:slime] to kill all slimes. Every little bit will help. (I am in Age 2) I followed a slime compass to a set of 3 adjacent slime chunks, built lit spawning platforms between Y0 and Y40, and no slimes ever spawned. I have lit up the room light levels are above 10 everywhere and there are no other mobs spawning inside. /kill @e [type=Slime] will kill all the Slimes in the world while leaving everything else alone. Not only should you find a large enough slime chunk, but it should also meet some of the conditions listed below. Slime ranching can be done with relative ease using decently lit areas to prevent other mobs from reducing the spawning rate of slimes. You need an absolute minimum of 6 layers. If you are lighting up a slime chunk, use regular torches since slimes spawn in any light level underground and a redstone torch only emits light level 7, so other mobs will spawn. I then added sugar, clocks, wool, chorus fruit, a nether star, a comparator, and a dragon egg to the spawner but nothing spawns from it. – MrLemon Feb 6, 2016 at 19:14 Add a comment 1 Answer Slimes are bouncy, cube-shaped hostile mobs that spawn deep underground in particular chunks, or in swamp biomes. Once you find a slime, note the location, you know they can spawn in that chunk. The reason is that the game checks for enough space for the big slime to spawn when it decides to spawn a slime so the spawn attempt will fail in these tunnels (i. Except in the swamps during moon phases. Slimes spawn in the Overworld in specific chunks below layer 40 regardless of light levels. For lighting use jack o' lanterns (much cheaper then sea lanterns, but you can use both), so that there isn't any spot in a platform that has light 7 or less because. Do /kill @e [type=!minecraft:player] (not !=) to kill everything that is not a player. I'm making an adventure map, and a recurring (and very irritating) problem is that Slimes spawn all over the place. I have code I've tinkered with that could be adapted find suitable slime free places to relocate the farm, provided I have the world seed, the size needed, and where the farm needs to be. [Verify] Big slimes require a 3×2½×3 space to spawn, small slimes require a 3×2×3 space, and tiny slimes require a 1×2×1 space (or 1×1×1 if the upper block is not opaque). 5 from 1. This mod displays in the F3 hud if your current chunk is a slimechunk. But after 2 hours of waiting no Slime spawned. 18, whereas slime spawns at any light level on or below 7 (there is a claim that. If you'd like to confirm, grab an entity xray addon from MCPEDL and test in a creative world. What about doing /locate and finding a swamp. • make an afk chamber at y134 at the golem's xz. So a crude test to see if there's no slime spawning at all would be to find a slime chunk, remove all blocks around it (within the server's view distance), create a floor at y=0, light it up and wait for spawns. You can create an artificially dark area by covering a section of the. Slime chunks are pretty rare. 2. In Minecraft, not every chunk is a slime chunk. Please note that my world used to be in 1. This mod expands your F3 screen to show the world seed (pre 1. Not in a superflat test world in slime chunks, not from slime water from tinkers construct, and not from the slimy tool modifier from tinkers (in fact, that modifier spawns a slime for half a second, before it vanishes). Slimes only spawn if the player is not within 32 blocks and the light level is between 0 and 7. Edit: It was because they only had a spawning space of 2 high instead of 3 high. I've dug out multiple different slime chunks (triple-checking with Chunkbase to make sure I had the correct coordinates), lit up surrounding caves, made sure the farms were made from spawnable blocks, but. I started at y-59 and noticed they weren't there so I went back up to y0 and tried all levels to y7 without results. Slimes will not spawn if they can see the sky. Tried making a slime farm but it isnt working. If you're adding floors inside the pyramid, the slimes will stop being an issue once you're above height. Slime spawners were working fine before but lately a player on my server has been afking at his Slime farm (with slime spawners) and noticed they aren't spawning. Apart from that and u being 24 blocks from where u want them to spawn, I dunno. Find a slime chunk close by. Mumbo Jumbo from hermitcraft tried this Swamp one and DocM77 keeps checking it regularly and it hadn't generated any slime but most people I see use chunks. Slimes can spawn in specific "slime chunks" below layer 40 of the Overworld. In short, my request is simply to prevent slime from spawning in the light, like all other hostile mobs. Seed:-8962506223096427993 Before building a slime farm, first decide whether to build it in a slime chunk or swamp biome. 19. 3) you can find the list of non-spawnable blocks and items placed. Might be a problem with bedrock again. Slimes not spawning [1. 25. ago. higher spawnrates). Yeah, it doesn't spawn slime on aternos servers for some reason. 3. You can stop them from spawning by lining the floor of your area with transparent blocks, such as glass or slabs. Slimes also spawn in swamp biomes between layers 51 and 69 under the condition that the light levels need to be seven or less since these layers are already. ago. Dig a 2x2 tunnel below Y40 through the chunks you're checking. 1 Answer. 10% of all chunks in your world are slime chunks. Share. To find out where you are, press F3. When slimes spawn they try to attack the golem and are killed by the cactus, dropping slimeballs onto the hoppers. Plus all the information on sl. Also be sure that your simulation distance is set to 4, you can choose this when creating a world or change this in the world settings. So I have cleared an area worth two chunks from surface down to bedrock with multiple platforms for them to spawn in that chunk. On my server, we are building a launch complex with Advanced Rocketry and goes to Bedrock. Chunkbase. as far as i know I’m doing everything right, ive lit up surrounding caves and my afk spot is at. It's not the light you. This can significantly affect the number of slimes that will spawn in a chunk. You can enter your world seed at a site like this, and it will work out which chunks in your world are Slime Chunks. So, you stand in. 2. You can enter your seed into the tool, and it will locate the chunks on your world that are slime chunks. Best to just make a farm with an iron golem bait, but I'm lazy sometimes. On the assumption that the seed is indeed correct, nothing is going to invalidate slime chunks. 24 blocks is at the edge of CAN SPAWN range. I used both minihud and ChunkBase to check the chunk. 2. Slime spawning in swamps can occur between Y=51 and Y=69. Make slimes spawn in dripstone caves. A slime is a rare hostile mob, which can spawn in three different sizes: big, small, or tiny. Slimes spawn in random underground chunks below Y=39 at any light level, and can also spawn in Swamp Biomes at night depending on the phase of the Moon. . 18. ExtraBiomes has others swamps that just don't spawn any slimes, sadly. SlimeSuppressor is a simple plugin that suppresses/disables slime spawning in slime chunks, potentially useful for superflat worlds. I even downloaded a slime chunk finding mod, and. However, slime chunks only allow. Additionally, the three sizes of slimes require. New moon won’t get you much of anything. Doesn't have to be a swamp. 1. As sb9884 pointed out, expand your farm upwards if you want more slime balls (and with the 1. Not only should you find a large enough slime chunk, but it should also meet some of the conditions listed below. It does not prevent spawners from working though, either normal Minecraft spawners or mod added like Cursed Earth. A 16 by 16 block area is represented as a chunk. Like lighting up all the caves in a 124 x 124 radius which is alot of work and you will likely miss alot. if you didnt miss a slime chunk it could be that the video you used is actualy showing you a farm that no. "Slime chunks" [edit | edit source] Slimes spawn throughout the world (except mushroom fields and deep dark biomes) below level Y=40 regardless of light level, but only in certain chunks; 1 ⁄ 10 of all. For lighting use jack o' lanterns (much cheaper then sea lanterns, but you can use both), so that there isn't any spot in a platform that has light 7 or less because. 5 high to spawn and 3. Follow. 19. I have been waiting for about an hour afk with the game active at around. No slimes for 30 minutes. Join. Seems the slimes have a hard time spawning in my multiple worlds as well. Aaryan2712 • 2 yr. Assuming your area is in the correct zone (inside a Slime. . Hey, I am trying to build a slime farm on my Minecraft server but the slimes aren't spawning AT ALL. It’s a predetermined area that will spawn slimes. Description. These chunks are rare and consist of only 10% of all in-game chunks. As mentioned before, use a slime in a bucket. The SlimeChunkF3 mod for Fabric worked, though. When the game attempts to spawn a hostile mob it has a chance of selecting to spawn a slime. 6, and slimes WERE spawning in the daytime. However, there aren't any slimes spawning. Share. I'll get roughly a stack of slime balls in 2-3 minutes with this method using Looting III. Slimes only spawn in certain slime chunks or swamp/mangrove swamp biomes. Slime Chunks are predetermined by your savegame seed, and are always the same for a specific seed, just like the generated. Slimes in swamps spawn between y51 and y69, regardless of slime chunks, most often at night, in light levels of 7 or less, and their spawning frequency changes with the moon cycle. Not only should you find a large enough slime chunk, but it should also meet some of the conditions listed below. Has anyone had any luck using the mini-map slime chunks, and if not what did you do?I have chosen 2 chunks next to each other to build the spawning pads, and used an non-slime chunk in front of them as the collection/lookout are. My conclusion is that you can have slimes spawn from below y40 all the way down to bedrock, but I need confirmation because I'm making a perimeter for a 4 chunk slime farm. Jul 17, 2016 at 22:03 @Alex no, I wanted to know what the top level of a slime farm should be for maximum efficiency, that can be found with data and so is not opinional. On average about 1 in every 10 chunks is a slime chunk, so a 4x4 chunk area should give you enough chunks to include at least one. I have waited for around 15 minutes exactly 32 block from the closest edge of the chunk with no spawns. Doing this will leave some room for slimes to spawn on. There are 16×16 blocks in each chunk (x and z axes) and 256 blocks in each chunk (y-axis). Mobs can't spawn within 24 blocks of the player, so by afking in the corner you lose a lot of spawning space. 5) to spawn, which size spawns is chosen relatively randomly and is impacted by your difficulty mode/regional difficulty level. ive used shulkercraft’s method but swapped out torches for lit jack-o-lanterns. Just make projects and work down there and you will get your Slime blocks. Maybe I need to put more info in my description. With this command in a Command Block, an automatic elimination of Slimes is possible: Just set it to Repeat and Always Active, and then you're done. Why is my slime chunk not spawning any slimes? : r/minecraft. ago. Mobs can't spawn closer than 24m to you (but despawn when farther away than 128m), so don't stand too close to where you expect them to spawn; It's a good idea to hollow out a 16x16 wide (= 1 chunk) and at least 3 blocks. 19 world. They will only spawn if you are within 16 to 144 blocks. Make sure the farm is the correct size. Hopefully this will show the layout (S = spawn chunk / X. that said, the Wiki seems to indicate that slimes can spawn on torches, or any other non-solid block (blocks you can move through):I know that Slimes can spawn in Swamp Biomes when the light level is below 7 and in any light level in 1/10 chunks when below Y=40. 4 with my friends and we wanted to build a slime farm. In slime chunks, the top spawning platform should be at y40. There may be other methods of blocking hostile mob spawns that I'm also not aware of that are more efficient. They spawn deep underground in chunks and also during the night in swamp biomes. Also lit up surrounding caves and ravines, although there might still be some areas that I have not lit up. If after a while they stop. I stayed several nights at swamps and saw no. Bruh-Bot9000. So while the overworld list contains things like creepers and zombies, the slime island list is just slimes of the proper type. So it's possible that slimes have spawned but despawned before they got killed. The server's render distance should be (sqrt. There are literally dozens of levels below where slimes are probably spawning (IF that is actually even a slime chunk at all). For reference, sea level is at the 65th layer. You just might have to dig up a lot more spawning platforms than pre 1. If you are still experiencing this issue in version 1. Find a dark spot. I'm not sure if this is the right section for this, but I have a question pertaining to Slime spawning. In Minecraft, not every chunk is a slime chunk. The easiest way to stop Slime chunks from spawning Slimes is using the commands suite to disable such activities. 16. Make sure there are no caves with zombies or any other mobs in the vicinity. #1. I found a nice back to back slime chunk near my base, hollowed both chunks out and below Y30 (max height for slimes to spawn) went down about 24 blocks or so, making layers every 4 blocks tall. We cover the. 18, changing it so most hostile overworld mobs need light level 0 to spawn, but slimes still spawn at levels up to 7. The game checks the following two factors before spawning a Slime: Light level is equal to or less than a random integer from 0 to 7. I take a look at the way slime spawn in Minecraft Java 1. To easily find a slime chunk in your seed, you can use Chunkbase. Also be sure that your simulation distance is set to 4, you can choose this when creating a world or change this in the world settings. Go underground until you arrive at Y40, then dig a 20-block-deep 16x16 chamber. You have NOt spawnproofed 128 blocks in all directions. You can create an artificially dark area by covering a section of the. " ~~~ MinecraftWiki article on Slimes. Slimes will not spawn within 24 blocks (spherical) of any player, and will despawn over time if no player is within 32 blocks and instantly if no. 16. Check if the farm has the correct conditions for slimes to spawn. Slime Spawn Mechanic. Note they didn't change anything about slime spawn rates in swamps. So I have cleared an area worth two chunks from surface down to bedrock with multiple platforms for them to spawn in that chunk. the light level of the spawning block must be 7 or darker (with exception. Slimes spawn less frequently than other hostile mobs, given identical ideal spawning conditions. I dug out a slime chunk and made a bubble elevator and drop to constantly go in and out of spawning range. The easiest way I found to stop slimes from spawning in bedrock edition is to make the floor out of some kind of glass that does include tinted glass so any type of glass. r/feedthebeast. A single cage was placed in a slime chunk, and is the only one of the. " Once those chunks are loaded, slimes can spawn anywhere from level 0 to level 10. To see the chunk that you are in, you can. Easiest way. Like most other hostile mobs, slimes do not spawn within 24 blocks (spherical) of any player, despawn over time if no player is within 32 blocks,. "4. The basic concept of building a Slime farm is simple: you need to find a Slime Chunk, dig out the entire Chunk, create platforms for the Slimes to spawn, and then have an efficient way of killing the Slimes and collecting the Slimeballs. However, lighting up the surrounding area does decrease the chances of non-slime mobs spawning and thus indirectly increases slime spawning rates. I'll dig out and see if there's a spawner somewhere. How do you increase slime spawn rate? #2 - Increase the spawn rate. Slime chunks are found below layer 40. Slimes can only spawn in designated "slime-chunks. Description. my45acp1911. Slimes have a low chance of spawning compared to all other mobs so if you havent spawnproofed EVERYTHING, they will barely spawn. Also my platforms are all just below the y 40 spawn limit, so idk if they get more common the deeper you go. The phases of the moon are also important. Light-emitting blocks may disable slimes spawning because of the light level changes surrounding them. It does not allow slime chunk spawns in swamps. (Use your wooden axe) 2 - Run the command /rg define <name>. So instead, I found a swamp biome. I even tried to clear out an entire chunk, to no avail. Slimes spawn on the SURFACE of a swamp during certain phases of the moon. If and when you find a slime underground, it must have spawned in a slime chunk, so press F3 + G (on. Witherstorm0156. Slime size is affected by regional difficulty: chances range from 33% for each size at low. Swamp farms are a bit faster than slime chunk farms. 2. The middle coordinate will show your vertical position. Java version 1. slimes spawn rarely unless nearby caves are all lit up or its the only spawnable space in ur despawn sphere . Also you need to be at least 28 blocks away and will need to light up any near. This is the case in a Swamp Biome from y=50 to y=70. Edit: right after posting this, I got 1 small slime spawn on the y-1 platform. The slime chunks are specific chunks that are rare and consist of only 10% of Minecraft world chunks. In slime Chunks they'll spawn like in the Version before this snapshot and in swamp Bioms to 0,0000000001%can't get slimes to spawn at all in slime chunk [Java] so I’ve built this massive slime farm in a slime chunk with a bunch of levels all the way from y-6 to y-40. Mob swab if you've never used it is and easy way. I have waited for around 15 minutes exactly 32 block from the closest edge of the chunk with no spawns. So i created a Aternos server in minecraft version 1. 18 (only 400 blocks around spawn is loaded in 1. Find a slime chunk close by. If no Slimes appear, it may be due to the chunk not being a Slime chunk. The easiest way I found to stop slimes from spawning in bedrock edition is to make the floor out of some kind of glass that does include tinted glass so any type of glass. Not possible because slimes only spawn in slime producing chunks. Slime Spawn Mechanic. Need a slime farm, so i found 4 slime chunks across eachother. If there is not a slime chunk there it will be near impossible to spawn slimes make shore t hat your farm is in one or it will not work . All sizes of slimes are hostile. Otherwise, carry around a spawn swap wand (the mod that has the charged diamonds) to capture a slime you come across eventually and put it in a normal spawner. Jul 29, 2019 2 0 0. Recently I used chunkbase to locate a slime chunk and dug the area out for the slime farm I'm planning on making. Only a certain number of them can spawn in a slime chunk so nametag them to prevent despawning and hide them somewhere in the chunk to prevent new slimes from spawning in. No slimes ever spawned. On the assumption that the seed is indeed correct, nothing is going to invalidate slime chunks. Slimes here will spawn between Y-level 50 and 70. Since slimes in slime chunks spawn below Y=40, regardless of the light level, in classic superflat worlds (top layer Y=4) there are always an awful lot of slimes which are really annoying and can sometimes. If you dig lower. (I am in Age 2) I followed a slime compass to a set of 3 adjacent slime chunks, built lit spawning platforms between Y0 and Y40, and no slimes ever spawned. They can also spawn in swamp biomes between layers 50-70 in light levels of 7 or less. On my server, we are building a launch complex with Advanced Rocketry and goes to Bedrock. Also, I'm doing this at night, no light sources, and I have never found any slimes in my world. Slimes spawn in specific chunks below layer 40. I started on y=11 and waited around by the chunk for anything to spawn, but nothing has, but I. 4 and the world is kinda corrupted) but no slimes are corrupting. If you’re on java, you can use f3 to check for slime chunks. The whole world of Minecraft is divided into thousands of chunks. As long as ur sure its a slime chunk they will spawn from y40 down to y 0. Each. They spawn below y=40 or between y=51-69 if in a swamp biome (but light level should be 7 or less) and it can’t be a new moon. Here's the one I have built most recently in 2 diagonally adjacent slime chunks. com to see if you're in a slime chunk. Oct 28, 2020. So, according to the information you have given, you are doing everything correctly, and Notch is simply not smiling down upon you. You can do this with the command /rg flag <name> deny-spawn slime. Since we started a new world on my server, only one slime has spawned in a swamp. Slime spawning and despawning uses different light and distance parameters from other 'hostile' mobs. • verify if the chunk is a slime chunk on a website (spoiler it is). The room is lit from 8-15 using jack-o-lanterns in the floor. In Minecraft, there is a certain limit to how many mobs can spawn in an area. Slime farms are light up to light level 8+ to prevent other types of mobs from spawning. In Minecraft, a “chunk” is a 16x16 segment of the game world. How do you increase slime spawn rate? #2 - Increase the spawn rate. I have lit up the room light levels are above 10 everywhere and there are no other mobs spawning inside. As you've only dug down to y37 and the game spawns mobs from bottom too the top of the world. In Superflat type worlds, the spawn rate is decreased. Ive made a gigantic slimefarm 16x24 all the way down to bedrock, and i left my pc on for an hour and nothing spawned, i was far enough that it could spawn and there were no mobs near as far as i knew and still nothing. Simply select your current version (such as Java 1. Wait for slimes to spawn and check which chunks they spawned into. However, the actual task of building it can be dangerous and difficult. The algorithm doesn't depend on the world seed, thus the chunks that slimes can naturally spawn in inhabit the same. They spawn more frequently during a full Moon, and never spawn during a new Moon.