Troubleshoot liquids not flowing into or out of tanks

Verify pipe connections

Make sure your BuildCraft pipes or ThermalDynamics tubes are actually touching the tank. Pipes must connect directly to the tank block's side. If the pipe is floating nearby, liquids won't transfer. Check that pipes aren't blocked by other blocks.

Check pump direction and power

BuildCraft pumps require power (Redstone Flux or BuildCraft energy) to operate. Verify your pump is powered and facing the correct direction. ThermalDynamics servos also need power. Without power, nothing flows.

Look for pipe gates or filters

If you've placed gates on your pipes, they might be blocking flow. Check gate conditions—they may be set to stop when tanks are full or empty. Adjust gate logic to allow liquids through when needed.

Ensure tank isn't full or empty

Tanks can only receive liquid if they have space, and can only output if they contain liquid. If a tank appears stuck, it may be completely full or completely empty. Manually add or remove liquid using a bucket to test.

Test with a bucket

Right-click a tank with a bucket to manually add or remove liquid. This confirms the tank itself works and helps isolate whether the problem is the tank or the pipes.