Are there any blocks that can detect/probe if a tube or pipe has any contents? Right now working on Mek 5x ore processing. I have a line of washers right now. I'd like to make it so when the clean slurry has been emptied out of the final pipe at the end of the line (up near the Chemical Crystallizer) a redstone signal is emitted to tell the pipe attached to the chest sending ore to the Dissolution Chamber to begin sending ore again. I have been having some backups here and there with ore slurry being jammed in the washers. I think I might have fixed it, but I'd like to be able to speed things up quite a bit! edit: Any way I can get the FMP blocks to not be darker than the other blocks? Here are a couple photos of the room and washers. Thanks!