I am planning to test their poop at the vet office and wanted to make sure that the vet is covering all possible situations. Interesting, they told me I can just bring a poop sample without the bird, and it's about $20+ per bird (fecal flotation)
He told me that one bird would be enough to test. If one bird has it, then a whole flock is treated.
Some of my birds have naked skin under their wings. But only those who are involved in a "love triangle" (Trillie, Stella, TaterTot), I assume it is nervous plucking? I think Trillie has had plucked underwings for a long time (he is the father)
Giardia is what needs to be checked?

The vet also said he can check them for Chlamydiosis (that can be passed to humans), this test is over a 100, I can't remember if its a poop or a blood test
I use bottled water for them.

Anything else that we need to be looking for?

Environmentally: house cleaning could have been better. I don't know if you remember how overwhelmed I have been. They like to land on the carpet and they sometimes land on the cement floor when they are in the outdoor aviary (which is simply at my porch). I try to prevent it but its not always I can. I line aviary floor with the cover, but it's not covering 100% of the cement. (the cover has some crazy patterns, I think they are scared of the cover, which is good). Simply, on a rare occasion some of my birds had landed on the bare cement of my front porch where we walk in street shoes and where any wild critters can freely step when aviary isn't set up (wild birds, for example, and who knows who else at night)

while I am logged in... every time I try to log in, I have some problems to get logged in. first, it takes forever to get a response (loading forever), then it tells me you have been redirected, then something else... I am surprised I am logged in now. Any ideas what is going on?

People have been reporting that it doesn't let you in on the window where you first logged in, but if you open a second window it will let you in. It has been doing this to me for a long time when I try to log in to the admin control panel, and now it's doing it to ordinary members too. I can't figure out how to fix it, and neither can tech support for the website. The forum is operating on an outdated platform, and it would take a huge amount of effort to update it. The group isn't active enough to make it worthwhile, and I don't mind if it fades away.

Giardia is a common cause of plucking under the wings so it's good to test for it, but you might not get an accurate answer. Giardia testing is tricky, because the parasite's presence in the poop is intermittent. The tests won't always find it even when there really is an infection.

Chlamydiosis (psittacosis) is more dangerous to humans than it is to birds. There's probably not much risk of this, and personally I wouldn't test for it unless I had a strong reason to suspect that it was there.

Thanks you!