First Off CONGRATS on the News of your Daughter!!!!
I really like the scape of the rocks and wood! And your plants seem to be coming along well! The crypts were probably grown immersed, like you said, if you purchased them on-line. Some people here also grow immersed plants, so I would check with who you bought them from! Melting is a normal thing for them though, even going from one tank to another in my aquariums has made a few different types go through a melting period! But usually you will see new growth in a week or so!
For your question/problem with the bubble count, I will try to help. I looked back in the journal and from the pics I can't tell what kind of needle valve you have. When I first started using pressurized Co2 I had a Cheepo Ice Maker Needle valve, and even though it worked, I had trouble adjusting it daily! I finally just started leaving it on 24-7 and running a air stone at night so the count wouldn't go haywire! Finally I went to a good needle valve , a Nibco nv-55 IIRC, and it has solved the problem! BUT even with a good needle valve it took a few days of playing with the pressure the regulator was set at and adjusting the needle valve to get it where I wanted it! I think it is set at 35# from the bottle was the sweet spot I finally found!
SO after all that spill, IF the needle valve is a good one, then you will probably need to play with the output pressure from the tank to get it to set where you want it! Sorry about the rambling!
On the lack of Ammonia, nitrite, nitrate, I would probably guess you still have good bacteria in it, and it is working on the food waste you are adding to the tank. OR it could be the plants, or a combo of both! BUT I would GO SLOW when adding fish, because with not much of a bio load in the tank the bacteria colony will "Shrink" to the amount of waste in the tank that it can feed on! So if you add a bunch of fish at one time it very well could start a Cycle since there won't be enough bacteria to take on a big load. At least that is in a fish only tank, but with plants you have a bit of a buffer "built in" but the plants can only consume so much!
Also since the filter was off for a extended amount of time the bacteria in it could have been killed off as well, so I would just recommend to go slow with fish or inverts!
Have you found the leak in the heater yet??? That would SCARE ME, BIG TIME!!! After seeing how much damage can come from a leaking canister filter overnight, I would FIND THE LEAK ASAP!!! A little water goes A LONG WAY on the floor!!!!
Well I hope I didn't talk your eyes dry!!! AWESOME NEWS on the Baby!!! We had a boy the first time out, and we stopped there, but I have 2 nieces, and I LOVE them to death!!! So I can only imagine having 2 Daughters!!! Yall are truly Blessed!!!
Holler back at me if you need any clarification on what I wrote! LOL Ya know Us Texas Boys have to stick together!!!
Best of luck, have a Merry Christmas!