In the short time I was there I talked to quite a few locals as well as the fishing tackle shops in Twizel. Almost all commented that the fishing in the canals has become much harder over the last few years. Discount my own experience as I really did not know how to interpret the local conditions nor the best methods and the best tools to apply them. I was just bloody lucky!!!
What I can tell you is the universal rule that when the fishing gets touch the most successful anglers are those who have learnt to think like fish and use the most appropriate gear for the job. While some of the fishing practices are pretty basic (i.e. soaking shrimps) other methods such as egg rolling are quite refined and require specialised gear, rod, line, sinker ultra fine tippets and 6mm egg imitations. I saw guys using 6lbs tippets trying to fool tackle wary 20-30lbs monsters. We are talking about the 10% who catch 90%. They have scaled down every part of their tackle as well have learnt from long experience.
What does that mean for all those visiting anglers who are lured to this area by intoxicating photos and videos of big fish harvest by all and sundry? Most only have a few days like myself and without help are almost guaranteed to leave disappointed.
I never thought I could bring myself to recommend hiring a guide but considering the total novelty of this fishery almost none of your previous trout fishing knowhow is of any value; not in the few days you have got anyway. If you can join one of the schools run by the Complete Angler or other providers than at least they will advise on the best time to make the trip, take you to places where it is happening at the time and show you all the tricks to secure a hook-up. This is a huge shortcut for the time-poor visitor. And just as important. Please don't make my mistake to skimp on the tackle.
Do the math of the cost of the whole trip and I can almost guaranty that what I have recommended is only a small fraction of the total. However if you want to have the best chance to secure the photo of your life time trophy than that fraction will be the most crucial to your success.
Cheers
Rainbow