Last Friday, after heavy rain on Thursday night, Lawrence and I again visited l’Aa at Ouve Wirquin, which in my view is perfection in a chalk stream. The river was running through fast, but clear enough. Typical of a healthy chalk stream, the Aa maintains a more or less constant flow rate, and colours only a little even after prolonged rain. Although there was no significant hatch (we saw only a trickle of pale wateries) we both could see fish nymphing in the shallows, though these were very difficult to approach, spooking at a fly line in the air or a too-hurried movement on the bank. Conditions were ideal though, with cloud cover, and very mild. Again we fished duo, with a sacrificial Oppo holding up a jig pattern. In two and a half hours we caught between us nine fish, and five of them were grayling! The biggest grayling was 43cm. So far as nymph fishing goes, I cannot possibly ask for more than l’Aa can yield to a very careful approach.Of course, one wishes that the fish were more often on the surface. I have only twice so far experienced strong enough hatches to lift the fish consistently to the surface. Nymph feeding prevails through much of each day. I can live with this on such a healthy river and there are opportunities enough for dry fly. Indeed, l’Aa has already taught me more about nymph fishing and I am enjoying this challenge a great deal. I think I need it, although Lawrence is not so sure!