Thanks guys!
I did a 40% water change yesterday and tested the water last night.
pH- still 7.8-7.9. I don't understand why a water change didn't raise it at all. Time to start considering a buffer, I s'pose.
Ammonia= 0
Nitrite= 0
Nitrate= 10
temp= 78
SG= 1.024
I think that since I just went open-top, I may have to top up twice a day to keep SG stable. I'm now keeping a pitcher of FW next to the tank for that, lol. Also, I am in the process of switching to RO water. My water change yesterday was part RO, part distilled.