BRS actually did a study on 90 degree vs 45 degree fittings and found no difference in GPH. I'm probably aiming on the low side for 10x turn over with that pump, but it's ultimately up to you. Some reefers prefer to generate all of their flow from wave makers and allow time for water to be processed in the sump. Some like higher turnover. You could very well be good and happy with the 10x!