I like to keep my FC on the high side. Is it harmful.
FC 4.3
CC 0
Ph 7.6
Hardness 170ppm
Alk 112
CYA 60
FC 4.3
CC 0
Ph 7.6
Hardness 170ppm
Alk 112
CYA 60
A timer will not cause a pump to run dry. You would have to have a massive air leak for the pump to run dry and that would present itself as a lot of air in the pump. The pump should not lose prime when it turns off. If it does, then you have a leak.
A timer would pay for itself and a new pump eventually just with the electrical savings. Not logical to me to be so concerned over something that you have never observed to be an actual problem. Up to you.
Another thing is (250000 gal / 3720 (which is hourly gallons filtered for my filter) x 2 = 13.4 hours. Looks like I am 1 hour short actually as I only do 12 hours. So I am saving as much as I can but running it at night and turning it off during day. And when i swim I change up the schedule and add a few more hours.