Got a cheap holder, sooo much better. No longer need to unclip to hit space bar on my laptop, lol.
According to Strava, hit 598 watts in today’s Champs race. Missed it by this much 
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Did Big Ring on Saturday as what I thought was a zone 2. Been basing zones on Garmin, which says sub 150 watts, but realize now it is too easy and really hard to stay there except by reducing my cadence more than I like. Looking at my power graph in Zwift for the ride, I see my zone 2 should be 150-175 watts, which I know is comfortable for me, lol. I just keep blundering around!
Anyway, I cannot see any way to manually change ftp in the Garmin connect site but I did move my Zwift ftp up a few points to 240 based on my recent 40 minutes production.
Oh, a complication is that the middle cogs on my cassette are damaged. Chain keeps jumping to smaller cogs. Not sure, but I might have done some damage when I first got the trainer and got in erg mode and experienced the death spiral a couple times before understanding what was going on! Anyway, ordered a new cassette after the ride.
You’ll find a User Settings tab when you look at your Device Settings. You can choose to base your HR Zones off a max HR value or a ‰LTHR.
There’s also field for Power Zones.
Will that do?
Hmm, I clicked on my device, Edge 25, at the web site. Nothing in device settings but found Heart Rate Zones under user settings. Sorry, it is not clear to me how to use the heart rate % fields to change ftp.
To be clearer, I do not see any way to directly input power zones.
You can’t set custom power zones in Zwift. Your zones are based off of percentages of your ftp.
I am not trying to set custom power zones in Zwift. I am trying to adjust power zones in Garmin Connect for viewing after rides. Of course, now that I noticed the graphs in Zwift my feed available by clicking on a finished ride it isn’t much of an issue anymore.
Did you try following this guide?
Thanks, I tried that guide before. At least on my iPad, there is nothing to scroll down below heart zones. I will check on my laptop.
Same result on laptop. Only can change heart rate zones. At least I cannot find anyway to switch to power zones.
Please do not trouble yourself about this matter, lol. The graph looks nice in Garmin, like I posted earlier, but I can just view the one in Zwift now that I know about it.
BTW, just a thought but maybe I cannot access power zones in Garmin Connect App or website because it is not supported on my old Edge 25. 
Yeah maybe so, but if you want to go further with it consider talking to Garmin support. They will be able to answer those questions very easily and their support is pretty good.
Yeah, maybe after I get my new cassette and trainer tire. Thanks to everyone for their suggestions.
Noticed a field on manual to check device. Does not apply to Edge 25.
And device is no longer supported.
Where can I find the % that zwift is using?
Hopefully this is still accurate…
Today, I finished the California challenge and reached level 30. So, I have a top aero frame and the best climbing frame. Next stop Tron bike. 
OTOH, clearly my precalibration power numbers were vastly inflated.
After resting next week, I plan on taking my first FTP test. Then maybe I can figure out a realistic zone training plan.