Hi BD.
I am glad to hear that you are using the "more modern" and "humane" method of cycling your tank.
I, too, have a 29gal, and have to admit it took me 5 weeks to complete the cycling process. The time frame does seem to vary in each case.
If you have been keeping a record in the little "sexy notebook" I suggested, and did indeed start with 5.0ppm, then a reading of 4 would indicate that it is proceeding.
ff makes a good point on the validity of your test kit. A simple experiment to test this would be to perform a test on tap or rainwater. It should show zero which indicates the kit is testing valid.
IMO, I would give it a little more time. I think you will be surprised once you start getting NitrIte readings, how quickly NitrAtes will follow. I do think that the "getting to NitrIte" part is the longest part of this process.
Verifying the temp to 80-85 degrees (no higher) aids in speeding this also.
Hang in there, my friend, you are doing fine.
Just think of all of the smiling faces on the new finned friends when you are able to introduce them to their healthy and comfortable envoirnment.
Bob