Hello Steve.
Breeding Odonata is really very easy. I use a simple glass fish tanks approx 2' x 1'x18" (usually bought from Car Boot Sales for a couple of pounds) with an air pump to keep the oxygen levels fairly high. A few pieces of Canadian Pondweed gives them somewhere to rest/hide/stalk from etc. The only problem is keeping up with enough live food. I usually use Copepods, Cyclops or similar small Crustations early in the year and Tadpoles when they become available, Small sticklebacks are also useful as a food source. They will also take small earthworms as they get larger. Fortunately, I have a small pond nearby which provides me with all the live food they need.
I remove all dead or partially consumed food each day and don't seem to have any problems seeing them through to the adult stage. If food is in short supply, they will eat each other, so it pays to add sufficient live food each day to keep them happy. When it comes to emergence time I use a few short lengths of roughened garden canes to give them a support. Never overcrowd them, this always seems to lead to canabalism.
Common Hawker nymphs from peaty pools in my area always seem to be black, yet after a moult in clear water they do change colour to a lighter shade of brown.
It really is simple to breed Dragonflies, especially those found in ponds, and nothing is more pleasurable than watching them feed or emerge.
I have three tanks on my windowsill each containing a range of Dragonfly species. I find it far more relaxing to watch them, than watching TV, and much better than watching goldfish swimming aimlessly around. lol.
Harry