You're right about the dye pH being way off and that will cause dyeing problems, but I think you have a connection problem.
Yeah I know; everyone's tired of hearing Mike and I harp about connections, we're tired of saying it too. You mention no hydrogen bubbles (it's hydrogen not air) forming on the work, and you have no agitation. No hydrogen forming means that no (or very little) anodization is occurring. The most likely suspect is the connections (again). A good test is to start the anodization and look closely at the work until you see some bubbles forming, then turn on the agitation. The bubbles will be visible within a few minutes of applying power. No bubbles means fix your connections. With some experience, you will be able to tell if this is OK with just a glance.
For a given anodic layer thickness, LCD will liberate just as much hydrogen as any other anodization process, but its spread over a longer time, so it looks like there is less hydrogen.
You should be using some form of agitation; it does promote even tank temperatures (always a good thing) but even more important, it will be tough to get an even coating without it.
Its easier to monitor PAR if you're using a constant current source rather than a voltage source, watching PAR is harder to do when you are busy constantly adjusting the voltage. The actual numbers you get are less important than having the right anodization curve; you should see a rapid rise in the voltage at the beginning, then a slow rise to PAR, and finally a slow fall in the voltage, indicating dissolution overtaking anodic growth.
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