diff --git a/src/main/java/com/cleanroommc/modularui/widgets/AbstractFluidDisplayWidget.java b/src/main/java/com/cleanroommc/modularui/widgets/AbstractFluidDisplayWidget.java
index 7bb0a15db..88953f966 100644
--- a/src/main/java/com/cleanroommc/modularui/widgets/AbstractFluidDisplayWidget.java
+++ b/src/main/java/com/cleanroommc/modularui/widgets/AbstractFluidDisplayWidget.java
@@ -16,6 +16,7 @@
 import net.minecraft.item.ItemStack;
 import net.minecraftforge.fluids.FluidStack;
 
+import com.gtnewhorizon.gtnhlib.util.numberformatting.NumberFormatConfig;
 import gregtech.api.util.GTUtility;
 import org.jetbrains.annotations.Nullable;
 
@@ -25,8 +26,8 @@ public abstract class AbstractFluidDisplayWidget<W extends AbstractFluidDisplayW
     public static final String UNIT_LITER = "L";
 
     private final Box contentPadding = new Box().all(1);
-    private String unit = UNIT_LITER;
-    private SIPrefix baseUnitPrefix = SIPrefix.One;
+    private @Nullable String unit = null;
+    private @Nullable SIPrefix baseUnitPrefix = null;
     private boolean flipLighterThanAir = true;
 
     protected AbstractFluidDisplayWidget() {
@@ -98,12 +99,21 @@ public final String getUnit() {
         return getBaseUnitSiPrefix().stringSymbol + getBaseUnit();
     }
 
+    /**
+     * @return the explicitly set base unit, or the one matching the fluid unit configured in GTNHLib
+     */
     public String getBaseUnit() {
-        return this.unit;
+        if (this.unit != null) return this.unit;
+        return usesMilliBuckets() ? UNIT_BUCKET : UNIT_LITER;
     }
 
     public SIPrefix getBaseUnitSiPrefix() {
-        return this.baseUnitPrefix;
+        if (this.baseUnitPrefix != null) return this.baseUnitPrefix;
+        return usesMilliBuckets() ? SIPrefix.Milli : SIPrefix.One;
+    }
+
+    private boolean usesMilliBuckets() {
+        return NumberFormatConfig.useForgeFluidMillibuckets;
     }
 
     public boolean isFlipLighterThanAir() {
diff --git a/src/main/java/com/cleanroommc/modularui/widgets/slot/FluidSlot.java b/src/main/java/com/cleanroommc/modularui/widgets/slot/FluidSlot.java
index 43da8ca26..1c60d0cd0 100644
--- a/src/main/java/com/cleanroommc/modularui/widgets/slot/FluidSlot.java
+++ b/src/main/java/com/cleanroommc/modularui/widgets/slot/FluidSlot.java
@@ -60,7 +60,7 @@ protected void addToolTip(RichTooltip tooltip) {
         if (this.syncHandler.isPhantom()) {
             if (fluid != null) {
                 if (this.syncHandler.controlsAmount()) {
-                    tooltip.addLine(IKey.lang("modularui2.fluid.phantom.amount", formatFluidTooltipAmount(fluid.amount), getBaseUnit()));
+                    tooltip.addLine(IKey.lang("modularui2.fluid.phantom.amount", formatFluidTooltipAmount(fluid.amount), getUnit()));
                 }
                 addAdditionalFluidInfo(tooltip, fluid);
             } else {
@@ -73,7 +73,7 @@ protected void addToolTip(RichTooltip tooltip) {
             }
         } else {
             if (fluid != null) {
-                tooltip.addLine(IKey.lang("modularui2.fluid.amount", formatFluidTooltipAmount(fluid.amount), formatFluidTooltipAmount(fluidTank.getCapacity()), getBaseUnit()));
+                tooltip.addLine(IKey.lang("modularui2.fluid.amount", formatFluidTooltipAmount(fluid.amount), formatFluidTooltipAmount(fluidTank.getCapacity()), getUnit()));
                 addAdditionalFluidInfo(tooltip, fluid);
             } else {
                 tooltip.addLine(IKey.lang("modularui2.fluid.empty"));
@@ -102,7 +102,6 @@ public void addAdditionalFluidInfo(RichTooltip tooltip, FluidStack fluidStack) {
 
     public String formatFluidTooltipAmount(double amount) {
         // the tooltip show the full number
-        // 1.7.10 hardcoded to use UNIT_LITER for now, so no milli-buckets.
         return TOOLTIP_FORMAT.format(amount);
     }