I have a Myers 1.5HP well pump for my sprinkler. It's about 10 years
old. Sitting outside in the elements, I cannot read too much on it
anymore. Seems to me that 10GPM is extremely low. Is it and if so,
could it be due to the pump being old? Could it be due to the well -
not supplying enough water. I'm in central Florida if that matters and
no rust from the well water. I have no idea how deep it is. It looks
like it's being fed with a 2" pipe.

Pressure and GPM were measured just after the pump out of a 3/4"
opening. It took 29 seconds to fill a 5 gallon bucket. 30PSI was
measured from the same spot. Although, 4 sprinkler heads were
"spraying" water down at the end of the run if that matters.

On a side note, it ran at least a couple of times for a few hours
without water - lost its prime somehow. It still functions though.