herns I appreciate the effort you have gone through organizing this picture and updating it over time. It is definitely helpful and I know a lot of people use this chart on different forums as the gold standard in diagnosing plants.
I think ultimately what I'd like to see happen with the plant deficiencies forum in the future is to take pictures of all species of aquatic plants during each deficiency mentioned above and organize it into the plantfinder. That way you can look up your plant on the plant finder, flip to nitrogen or phosphate deficiency (etc...) and see what it looks like with your specific species. We already have something like this on APC, but it isn't incorporated into the plantfinder and its not very thorough or updated very often. It is sort of on its own floating out there on its own. I'll have to see if we can reorganize things so everything is in one place.
Oh, also, if you get a chance in your next update of the figure could you correct my name from ZapKins to Zapins.