So I brew all grain- no pumps, no tiers- just a pitcher to measure and move mash/sparge water around and I use my keggle as both my HLT and BK. Question- when you use a gravity system or a pump system, how do you measure/regulate the amount of water you are pushing from one vessel to another? Are you simply eyeballing the site tube? It seems like I have seen photos of both gravity and pump systems without site tubes on the HLT.