First Fishless Cycle - Low pH "Stalling" the cycle?

Hi everyone! This is my first post here, so please be patient with me!

I am fishless cycling my 29 gallon tank right now. I had a fish tank for several years as a teenager, but I made all the typical newbie mistakes and eventually gave up the hobby when I moved out. Recently I decided to get back into fishkeeping. This time I've been determined to do it "right" and so I did a ton of research before buying my tank and continue to do so as I'm fishless cycling.

Here's a few details I know will probably be asked:
-I set up the tank & used dechlored water via API Tap Water Conditioner
-I have been using ACE's brand of clear Ammonia (10% ammonia hydroxide - nothing else added)
-I have a Whisper Power Filter with the basic white "floss" filter cartridge & nothing added (no charcoal, etc.)
-My temperature is set at 85 degrees and I am running a sponge filter in the corner (to keep seeded for my Q-tank) and I am keeping the water level a couple inches lower
-My city water - kH is 4, GH is 53.7
-Baseline pH is 6.8 out of tap and 7.4 after being treated with conditioner and sitting for 24-48 hours.
-I have been using the API Freshwater Master Test Kit for all my tests
-I did not have access to any "seeding" material - I don't trust the LFS (petco, etc.) and don't have any friends with fish tanks, so I have started from scratch
-Please know that I am not impatient about this, I will wait as long as necessary to get this tank cycled properly before adding fish.

Here's my cycle "journal" so far:
Day 1 - added ammonia
Day 3 - realized ammonia was actually 8 ppm (or possibly higher) and did a 15% water change, bringing the ammonia level down to 5 ppm
Day 11 - Ammonia 4 ppm, nitrites .25 ppm
Day 13 - Ammonia 3 ppm, nitrites .25 ppm
Day 19 AM - Ammonia 2 ppm, nitrites 2 ppm
Day 19 PM - Ammonia 1 ppm, nitrites 4 ppm - added ammonia
Day 20 AM - Ammonia 0 ppm, nitrites 4 ppm - added ammonia to bring to 4 ppm
Day 20 PM - Ammonia .25 ppm, nitrites 4 ppm, nitrates 5 ppm, pH 7.4 - added ammonia
Day 21 AM - Ammonia 0 ppm, nitrites 1 ppm, nitrates 5 ppm - added ammonia
Day 21 PM - Ammonia 0 ppm, nitrites 1 ppm, nitrates 5 ppm - added ammonia
Day 22 AM - Ammonia .50 ppm, nitrites .50 ppm, nitrates 5-10 ppm
Day 22 PM - Ammonia .25 ppm, nitrites .50 ppm, nitrates 5 ppm - added ammonia (4 ppm)
Day 23 AM - Ammonia 2.0 ppm, nitrites .25-.50 ppm, nitrates 5 ppm
Day 23 PM - Ammonia 2.0 ppm, nitrites .25-.50 ppm, nitrates 5 ppm
50 % water change (dechlored water) added ammonia
Day 24 AM - Ammonia 0 ppm, nitrites 1 ppm, nitrates 0 ppm - added ammonia
Day 24 PM - Ammonia 0 ppm, nitrites 1 ppm, nitrates 0-5 ppm - added ammonia
Day 25 AM - Ammonia .25 ppm, nitrites .50 ppm, nitrates 0-5 ppm
Day 25 PM - Ammonia 0 ppm, nitrates .50 ppm, nitrates 10 ppm - added ammonia
Day 26 AM - Ammonia 2 ppm, nitrites .50 ppm, nitrates 0-5 ppm
Day 26 PM - Ammonia 2 ppm, nitrites .50 ppm, nitrates 5 ppm, pH 6.0
Day 27 (TODAY) AM - Ammonia 1 ppm, nitrites .50 ppm, nitrates 0-5 ppm, pH 6.0
25% water change (dechlored water), retested levels - Ammonia 1 ppm, pH 6.8, added ammonia
Also tested tank kH - 2.0 / gH 71.6


My question - is the low pH harming or at least somewhat stalling the growth of bacteria? I haven't tested the pH more throughout the cycle as I read that it will fluctuate a lot and it isn't necessarily that important at this point. However upon seeing my ammonia-eating-bacteria dropping off and seeing that my pH is becoming quite acidic, I'm inclined to think that because I have softer water, it is indeed an issue and is stalling the cycle or at least really slowing it down. As you can see from the time I did test the pH, when the ammonia levels started coming down to 0 within 12 or 24 hours, it was higher - 7.4 - and then the bacteria slowed and then increased again after a water change (which I'm guessing upped the pH level.) When they once again slowed down, the pH was very acidic. I'm very interested to see if the ammonia levels drop down quicker when I test this evening as the pH is once again higher.

So if my theory is correct, what should I do to stabilize the pH? I've read about using crushed coral, but the petstore didn't have any. I also heard baking soda mentioned a few times when I was doing a search on here, but that seems to be a short-term solution. Would that work for now or would a longer-term solution like the crushed coral be better in my case?
Any tips? Advice?

Thank you!

After doing a bunch of searches on this forum, I think it's my low alkalinity that's my problem vs the low pH.

My tap water kH is 4 and after testing my kH earlier (AFTER a partial water change), it was just 2. That's pretty low and it was probably even lower before the water change.

Here's a link to a previous post on here and it sounds very much like my problem:
http://www.aquariacentral.com/forums/showthread.php?t=66570&highlight=cycling+buffering


Judging from this post and the people who responded, it seems that I need to do more frequent water changes to keep the alkalinity higher... That would certainly be safer and less risky IMO than adding baking soda too.

Any opinions on this...?