So, I just started fooling around more with Forestry, and I tried to open the Squeezer, and this happened:

---- Minecraft Crash Report ----
// I bet Cylons wouldn't have this problem.

Time: 4/27/15 10:02 PM
Description: Unexpected error

java.lang.IllegalArgumentException: Cannot create a fluidstack from a null fluid
at net.minecraftforge.fluids.FluidStack.<init>(FluidStack.java:36)
at net.minecraftforge.fluids.FluidStack.<init>(FluidStack.java:67)
at forestry.core.fluids.TankManager.processGuiUpdate(TankManager.java:232)
at forestry.core.gui.ContainerLiquidTanks.func_75137_b(ContainerLiquidTanks.java:90)
at net.minecraft.client.network.NetHandlerPlayClient.func_147245_a(NetHandlerPlayClient.java:1151)
at net.minecraft.network.play.server.S31PacketWindowProperty.func_148833_a(SourceFile:26)
at net.minecraft.network.play.server.S31PacketWindowProperty.func_148833_a(SourceFile:9)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273)
at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1591)
at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:962)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:887)
at net.minecraft.client.main.Main.main(SourceFile:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at net.minecraftforge.fluids.FluidStack.<init>(FluidStack.java:36)
at net.minecraftforge.fluids.FluidStack.<init>(FluidStack.java:67)
at forestry.core.fluids.TankManager.processGuiUpdate(TankManager.java:232)
at forestry.core.gui.ContainerLiquidTanks.func_75137_b(ContainerLiquidTanks.java:90)
at net.minecraft.client.network.NetHandlerPlayClient.func_147245_a(NetHandlerPlayClient.java:1151)
at net.minecraft.network.play.server.S31PacketWindowProperty.func_148833_a(SourceFile:26)
at net.minecraft.network.play.server.S31PacketWindowProperty.func_148833_a(SourceFile:9)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.client.multiplayer.PlayerControllerMP.func_78765_e(PlayerControllerMP.java:273)

-- Affected level --
Details:
Level name: MpServer
All players: 1 total; [EntityClientPlayerMP['AlienDoesMC'/274, l='MpServer', x=-289.00, y=71.62, z=-9.06]]
Chunk stats: MultiplayerChunkCache: 576, 576
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (-252,64,-28), Chunk: (at 4,4,4 in -16,-2; contains blocks -256,0,-32 to -241,255,-17), Region: (-1,-1; contains chunks -32,-32 to -1,-1, blocks -512,0,-512 to -1,255,-1)
Level time: 1193 game time, 1193 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false
Forced entities: 82 total; [EntitySquid['Squid'/128, l='MpServer', x=-259.06, y=58.34, z=21.91], EntitySquid['Squid'/129, l='MpServer', x=-260.84, y=60.38, z=20.22], EntitySquid['Squid'/130, l='MpServer', x=-267.19, y=59.34, z=21.38], EntitySquid['Squid'/131, l='MpServer', x=-260.63, y=55.31, z=27.78], EntitySquid['Squid'/132, l='MpServer', x=-267.19, y=58.38, z=27.22], EntitySquid['Squid'/133, l='MpServer', x=-259.84, y=58.25, z=28.06], EntitySquid['Squid'/134, l='MpServer', x=-265.78, y=58.00, z=41.16], EntitySquid['Squid'/135, l='MpServer', x=-265.50, y=57.94, z=37.75], EntitySquid['Squid'/136, l='MpServer', x=-272.25, y=60.34, z=36.97], EntitySquid['Squid'/137, l='MpServer', x=-263.03, y=58.38, z=44.09], EntitySquid['Squid'/138, l='MpServer', x=-272.31, y=59.34, z=40.56], EntitySquid['Squid'/139, l='MpServer', x=-269.63, y=57.91, z=40.53], EntitySquid['Squid'/140, l='MpServer', x=-261.66, y=59.19, z=56.25], EntitySquid['Squid'/141, l='MpServer', x=-256.59, y=60.09, z=51.44], EntitySquid['Squid'/142, l='MpServer', x=-264.66, y=54.81, z=54.25], EntityCow['Cow'/146, l='MpServer', x=-255.81, y=68.00, z=-52.78], EntityCow['Cow'/147, l='MpServer', x=-249.22, y=64.00, z=-49.44], EntityCow['Cow'/148, l='MpServer', x=-245.28, y=64.00, z=-57.50], EntityCow['Cow'/149, l='MpServer', x=-248.50, y=64.00, z=-47.50], EntitySquid['Squid'/150, l='MpServer', x=-254.47, y=56.28, z=24.91], EntitySquid['Squid'/151, l='MpServer', x=-247.59, y=53.69, z=23.66], EntitySquid['Squid'/152, l='MpServer', x=-253.50, y=56.16, z=35.66], EntityBat['Bat'/160, l='MpServer', x=-212.56, y=26.10, z=-63.41], EntityBat['Bat'/161, l='MpServer', x=-220.38, y=24.10, z=-38.56], EntityBat['Bat'/162, l='MpServer', x=-215.75, y=22.82, z=-17.25], EntityCow['Cow'/42, l='MpServer', x=-355.16, y=70.00, z=-32.84], EntityCow['Cow'/43, l='MpServer', x=-359.19, y=70.00, z=-29.30], EntityCow['Cow'/44, l='MpServer', x=-357.13, y=70.00, z=-29.69], EntityCow['Cow'/45, l='MpServer', x=-354.50, y=70.00, z=-30.50], EntityBat['Bat'/55, l='MpServer', x=-350.91, y=57.89, z=-65.31], EntityBat['Bat'/56, l='MpServer', x=-330.17, y=19.58, z=-53.25], EntityClientPlayerMP['AlienDoesMC'/274, l='MpServer', x=-289.00, y=71.62, z=-9.06], EntityBat['Bat'/62, l='MpServer', x=-334.25, y=20.10, z=-60.25], EntitySquid['Squid'/63, l='MpServer', x=-331.50, y=47.13, z=26.09], EntitySquid['Squid'/64, l='MpServer', x=-328.31, y=51.38, z=26.91], EntitySquid['Squid'/65, l='MpServer', x=-321.97, y=48.00, z=31.41], EntitySquid['Squid'/66, l='MpServer', x=-323.59, y=48.16, z=26.50], EntitySquid['Squid'/67, l='MpServer', x=-331.97, y=49.06, z=35.59], EntitySquid['Squid'/68, l='MpServer', x=-328.59, y=48.22, z=24.19], EntitySquid['Squid'/69, l='MpServer', x=-325.06, y=50.38, z=30.59], EntitySquid['Squid'/70, l='MpServer', x=-327.53, y=49.34, z=24.13], EntitySquid['Squid'/71, l='MpServer', x=-337.09, y=46.91, z=24.53], EntitySquid['Squid'/72, l='MpServer', x=-329.16, y=48.88, z=18.91], EntitySquid['Squid'/73, l='MpServer', x=-334.63, y=55.81, z=40.19], EntitySquid['Squid'/74, l='MpServer', x=-329.63, y=56.09, z=33.28], EntitySquid['Squid'/75, l='MpServer', x=-324.56, y=60.22, z=39.09], EntitySquid['Squid'/76, l='MpServer', x=-326.47, y=55.38, z=33.91], EntitySquid['Squid'/77, l='MpServer', x=-330.13, y=55.03, z=45.03], EntitySquid['Squid'/78, l='MpServer', x=-328.50, y=60.38, z=32.06], EntitySquid['Squid'/79, l='MpServer', x=-331.38, y=58.72, z=33.53], EntitySquid['Squid'/84, l='MpServer', x=-321.69, y=49.00, z=23.38], EntitySquid['Squid'/85, l='MpServer', x=-302.81, y=50.88, z=33.53], EntitySquid['Squid'/86, l='MpServer', x=-311.03, y=53.31, z=26.41], EntitySquid['Squid'/87, l='MpServer', x=-321.16, y=49.75, z=16.84], EntitySquid['Squid'/88, l='MpServer', x=-305.78, y=54.00, z=29.59], EntitySquid['Squid'/89, l='MpServer', x=-305.50, y=52.34, z=26.09], EntitySquid['Squid'/90, l='MpServer', x=-311.56, y=48.16, z=26.63], EntitySquid['Squid'/91, l='MpServer', x=-306.16, y=56.28, z=33.66], EntityBat['Bat'/92, l='MpServer', x=-305.59, y=26.26, z=45.53], EntitySquid['Squid'/93, l='MpServer', x=-322.56, y=49.38, z=42.88], EntitySquid['Squid'/94, l='MpServer', x=-299.88, y=47.31, z=31.94], EntitySquid['Squid'/95, l='MpServer', x=-295.41, y=48.78, z=18.66], EntitySquid['Squid'/96, l='MpServer', x=-300.56, y=51.00, z=23.78], EntitySquid['Squid'/97, l='MpServer', x=-296.19, y=49.38, z=29.53], EntitySquid['Squid'/98, l='MpServer', x=-302.97, y=53.22, z=31.66], EntitySquid['Squid'/99, l='MpServer', x=-294.56, y=50.81, z=25.91], EntitySquid['Squid'/100, l='MpServer', x=-299.28, y=50.38, z=31.44], EntitySquid['Squid'/101, l='MpServer', x=-302.88, y=51.22, z=26.81], EntitySquid['Squid'/102, l='MpServer', x=-292.94, y=51.34, z=30.66], EntitySquid['Squid'/103, l='MpServer', x=-295.34, y=49.38, z=38.59], EntitySquid['Squid'/104, l='MpServer', x=-300.47, y=51.38, z=30.53], EntitySquid['Squid'/105, l='MpServer', x=-299.06, y=45.69, z=27.59], EntitySquid['Squid'/106, l='MpServer', x=-301.69, y=50.25, z=35.38], EntitySquid['Squid'/107, l='MpServer', x=-305.50, y=50.25, z=38.44], EntityBat['Bat'/113, l='MpServer', x=-272.09, y=12.27, z=-26.63], EntityBat['Bat'/114, l='MpServer', x=-263.47, y=11.92, z=-24.97], EntityBat['Bat'/115, l='MpServer', x=-262.59, y=11.86, z=-16.97], EntitySquid['Squid'/116, l='MpServer', x=-272.88, y=60.75, z=52.63], EntityBat['Bat'/124, l='MpServer', x=-263.88, y=12.20, z=-10.84], EntitySquid['Squid'/125, l='MpServer', x=-254.53, y=60.34, z=26.56], EntitySquid['Squid'/126, l='MpServer', x=-253.50, y=53.22, z=22.69], EntitySquid['Squid'/127, l='MpServer', x=-262.66, y=57.00, z=31.19]]
Retry entities: 0 total; []
Server brand: fml,forge
Server type: Integrated singleplayer server
Stacktrace:
at net.minecraft.client.multiplayer.WorldClient.func_72914_a(WorldClient.java:373)
at net.minecraft.client.Minecraft.func_71396_d(Minecraft.java:2433)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:916)
at net.minecraft.client.main.Main.main(SourceFile:148)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)

-- System Details --
Details:
Minecraft Version: 1.7.10
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0_31, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 172954304 bytes (164 MB) / 538685440 bytes (513 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 1, tcache: 0, allocated: 12, tallocated: 96
FML: MCP v9.05 FML v7.10.118.1389 Minecraft Forge 10.13.3.1389 11 mods loaded, 11 mods active
mcp{9.05} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
FML{7.10.118.1389} [Forge Mod Loader] (forge-1.7.10-10.13.3.1389-1710ls.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Forge{10.13.3.1389} [Minecraft Forge] (forge-1.7.10-10.13.3.1389-1710ls.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Core{6.2.6} [BuildCraft] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Transport{6.2.6} [BC Transport] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Silicon{6.2.6} [BC Silicon] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Builders{6.2.6} [BC Builders] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Energy{6.2.6} [BC Energy] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BuildCraft|Factory{6.2.6} [BC Factory] (buildcraft-6.2.6.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
IC2{2.2.717-experimental} [IndustrialCraft 2] (industrialcraft-2-2.2.717-experimental.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Forestry{3.5.3.11} [Forestry for Minecraft] (forestry_1.7.10-3.5.3.11.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
GL info: ' Vendor: 'ATI Technologies Inc.' Version: '2.1.8787' Renderer: 'ATI Mobility Radeon HD 4500 Series'
Launched Version: 1.7.10-Forge10.13.3.1389-1710ls
LWJGL: 2.9.1
OpenGL: ATI Mobility Radeon HD 4500 Series GL version 2.1.8787, ATI Technologies Inc.
GL Caps: Using GL 1.3 multitexturing.
Using framebuffer objects because ARB_framebuffer_object is supported and separate blending is supported.
Anisotropic filtering is supported and maximum anisotropy is 16.
Shaders are available because OpenGL 2.1 is supported.

Is Modded: Definitely; Client brand changed to 'fml,forge'
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)
Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Anisotropic Filtering: Off (1)

Recreate: I placed a squeezer down, right clicked it, and the game froze, said "Shutting down internal server", and crashed.