That's a little long for my liking , I do my personal one's every 6 months. I recommend customers to do there's 1/year Minimum. Cheap Insurance!I have been using $70 Racor filters with water separation for a long time. One that I now use on a 22'2" Aquasport. came on an 87 Dusky. The 10 micron filter cartridges cost less than $30 and I change them about once every 2 or 3 years.