How long to dry hop? losing aroma fast

Hi
This is my 2nd dry hopped beer, this time a Denny's Rye IPA approximation, and I dry hopped in the secondary for 3 days w/ an ounce of Summit leaf. Now that the beer has got into the keg and was tasting just a bit shy of what I wanted in aroma, I dropped in an ounce of cascade leaf, in a medium grain bag, in the cold , 2/3 full corny keg. 10 hours later the difference was amazing. The next day, heavenly hops flavor, now a couple days later (4 days total, I think) the aroma seems to be really diminished, and seems more "dank?". It still tastes good but nothing like it did the day before.
I've seen some recipes call for a week of dry hop and some for just a couple days. Did I miss the boat for removing the hops? I am about to remove them but I'd like to know better for next time.
I did a search but "dry hop hopping time how long" etc are VERY common words here and did not seem to target my question.
-Ben

When I dry hop in the keg I don't remove the bag until the keg is drained. Some say this promotes grassy flavors but my beer is never grassy like a lot of commercial dryhopped beers are. After about 1-2 weeks the flavor will meld with the beer and it will taste far different than it did today. Normal dry hopping is one week. RDWHAHB

I guess so. I had just pulled the bag and the hops were still bright and bitter tasting but the aroma was minimal.
The beer is good but NOTHING like it was for the first 3 days.

hops wont release any bittering during dryhopping. It takes the boil and isomerzation (sp) to make a bittering addition. If you want to make it more bitter I would boil some hops in a small amount of water, then add the water. The amount and time of boil would have to be trial and error to get what you were looking for. Late additions for flavor and aroma are oftern the hardest to nail down due to low utilization from SG and hop bags. good luck

The most volatile aroma oils fade fast. Sounds like you need a Randall, but you'd have to change the hops every day.

I just noticed some of my edwort apfelwien had backed up into the IPA keg. I don't think a lot, but some was definitely in the co2 line. This could explain the different flavor. I will need to clean my co2 lines, manifold, etc. Odd thing is they are all at the same pressure, and each line has it's own check valve shutoff.
And yes it was the aroma that had faded, the bitterness is fine. It had some of that sierra nevada nose, and then disappeared.