Thank you all very much.
I measured pH just before I turned the lights off it was 7.0 - 7.1 (hard to tell exactly), and again I checked first thing in the morning before I turned the lights on and it was 6.8 (maybe a touch higher). So that is less than a .8 swing and as long as it stays around there that is all good correct? I check the CO2 chart and at 7.1 its about 12ppm CO2 and at 6.8 it is about 24, so all very good. (woohoo!)
I will continue to check the KH and it is fun watching the CO2 bubbles go up the ladder. My watersprite is pearling, the fish look happy, I get to go watch what the plants do for the next few weeks.
Isn't this all amazing? I have learned more chemistry in the last 4 weeks that I ever did in high school!
My hubs and kids listen patiently whilst I babble on about low nitrates and mixing KNO3 and trace elements and CO2, but they do like to watch the bubbles and the fish too!
2.5 gallon heated filtered - betta Nemo
2.5 gallon heated filtered - betta Marlin
10 gallon planted, heated, ACmini
3 pygmy corys (to come)
2 cherry barbs (to come)