Time how long it takes to flow 5 gallons into bucket. Divide time by 5. Now you know how many gallons per minute your water hose is flowing. Dump first bucket in , then time it till full. Easy to figure out when you know how nany GPM' s your hose is flowing.
'98 Tr20 Triton completly updated & rigged, 05 Magnum c-channeltrailer
'94 Merc 200Xri completly rebuilt & noseconed/low water pickup lower unit.