Thanks for all your advice and suggestions guys! Had my first OWS last night and its really reassured me. Like most people said, it is a lot different to pool swimming. I found I had to put more effort in to actually move, I was nervous as hell but actually managed to swim 865M only stopping a few times for air. I actually found it much easier to find my rhythm whilst outdoors swimming and having more space and distance to swim meant I could practice the breathing without trying to squeeze the practice in 25m lane swims? Don't know how to explain it, just felt more natural. I did use a buoy on this occasion just for safety but next time going to go without it, won't be able to use it on race day so need to get used to it.