Assuming your filter guage is correct, with a filter presure of 10 PSI, I suspect you actually have a head loss of much less than you think. Return loss is 23 feet and suction loss usually does not exceed 15 feet so you may be closer to 40 or 45 feet at the most. So your flow may be closer to 80 GPM.

You said the filter design rate is 44 GPM but is that the maximum recommended rate? If so, then you may have a concern.